<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019ffbb6-86ba-732e-a33a-e96c7ec43317,g:42be06e0-42db-461d-83d0-32a415af58d7-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://ir.barings.com/role/ConsolidatedBalanceSheets" xlink:type="simple" xlink:href="bbdc-20260930.xsd#ConsolidatedBalanceSheets"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/ConsolidatedBalanceSheets" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7318-a283-ebdee38a934b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019ffbb6-9f65-74b8-8c2d-8251dda8a29d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7318-a283-ebdee38a934b" xlink:to="loc_us-gaap_StatementTable_019ffbb6-9f65-74b8-8c2d-8251dda8a29d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7ef3-8e96-887aeceff4f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f65-74b8-8c2d-8251dda8a29d" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7ef3-8e96-887aeceff4f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7ef3-8e96-887aeceff4f6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7ef3-8e96-887aeceff4f6" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7ef3-8e96-887aeceff4f6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7431-8f33-ccde1269272c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7ef3-8e96-887aeceff4f6" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7431-8f33-ccde1269272c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f65-7e19-a4de-925fd231ea82" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentUnaffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7431-8f33-ccde1269272c" xlink:to="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f65-7e19-a4de-925fd231ea82" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f65-7bf3-adbf-a118300dd6c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7431-8f33-ccde1269272c" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f65-7bf3-adbf-a118300dd6c7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f65-7b2f-bcca-273815ea4437" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7431-8f33-ccde1269272c" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f65-7b2f-bcca-273815ea4437" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f65-7208-b6fe-c1a24a051551" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f65-74b8-8c2d-8251dda8a29d" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f65-7208-b6fe-c1a24a051551" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-7208-b6fe-c1a24a051551_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f65-7208-b6fe-c1a24a051551" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-7208-b6fe-c1a24a051551_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-71bd-a181-860753363ade" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f65-7208-b6fe-c1a24a051551" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-71bd-a181-860753363ade" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f65-7190-b6ad-0fe726fa4c93" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-71bd-a181-860753363ade" xlink:to="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f65-7190-b6ad-0fe726fa4c93" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019ffbb6-9f65-7e63-806d-90bbf9e3a332" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-71bd-a181-860753363ade" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019ffbb6-9f65-7e63-806d-90bbf9e3a332" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7318-a283-ebdee38a934b" xlink:to="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-9f65-7f35-b552-6a1951511aa6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-9f65-7f35-b552-6a1951511aa6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashNotHeldInForeignCurrency_019ffbb6-9f65-7e8e-a7d6-859b405bca32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashNotHeldInForeignCurrency"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_CashNotHeldInForeignCurrency_019ffbb6-9f65-7e8e-a7d6-859b405bca32" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashHeldInForeignCurrency_019ffbb6-9f65-70a7-9acf-5d66f7e0d4d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashHeldInForeignCurrency"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_CashHeldInForeignCurrency_019ffbb6-9f65-70a7-9acf-5d66f7e0d4d7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendAndInterestReceivable_019ffbb6-9f65-7d63-b692-d6e205931ff8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendAndInterestReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_DividendAndInterestReceivable_019ffbb6-9f65-7d63-b692-d6e205931ff8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssets_019ffbb6-9f65-7e89-9734-cec93cec2e28" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssets_019ffbb6-9f65-7e89-9734-cec93cec2e28" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019ffbb6-9f65-7b65-8a8f-a0d7677e43bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_DerivativeAssets_019ffbb6-9f65-7b65-8a8f-a0d7677e43bb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtIssuanceCostsLineOfCreditArrangementsNet_019ffbb6-9f65-790e-b51f-971a64c401b3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtIssuanceCostsLineOfCreditArrangementsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_DebtIssuanceCostsLineOfCreditArrangementsNet_019ffbb6-9f65-790e-b51f-971a64c401b3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivableInvestmentSale_019ffbb6-9f65-772c-9a2e-3313e8327527" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReceivableInvestmentSale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_ReceivableInvestmentSale_019ffbb6-9f65-772c-9a2e-3313e8327527" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019ffbb6-9f65-7b00-9ef3-609e0f6b30cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019ffbb6-9f65-7eff-a4f1-fa89331f9b9c" xlink:to="loc_us-gaap_Assets_019ffbb6-9f65-7b00-9ef3-609e0f6b30cd" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7318-a283-ebdee38a934b" xlink:to="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent_019ffbb6-9f65-74b1-a6ad-830aa678fa51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent_019ffbb6-9f65-74b1-a6ad-830aa678fa51" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestPayableCurrentAndNoncurrent_019ffbb6-9f65-7d4a-8510-d9f1c0934197" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestPayableCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_InterestPayableCurrentAndNoncurrent_019ffbb6-9f65-7d4a-8510-d9f1c0934197" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AdministrativeFeesPayable_019ffbb6-9f65-7a72-a55c-07888e5335e2" xlink:href="bbdc-20260930.xsd#bbdc_AdministrativeFeesPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_bbdc_AdministrativeFeesPayable_019ffbb6-9f65-7a72-a55c-07888e5335e2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeePayable_019ffbb6-9f65-7afa-9393-4c314a7445c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementFeePayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_ManagementFeePayable_019ffbb6-9f65-7afa-9393-4c314a7445c8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncentiveFeePayable_019ffbb6-9f65-752d-b7b2-1e2ed9fb8eb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncentiveFeePayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_IncentiveFeePayable_019ffbb6-9f65-752d-b7b2-1e2ed9fb8eb5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019ffbb6-9f65-706d-a634-9b92945f4691" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_DerivativeLiabilities_019ffbb6-9f65-706d-a634-9b92945f4691" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PayableInvestmentPurchase_019ffbb6-9f65-7547-ab13-4a043f39e0fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PayableInvestmentPurchase"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_PayableInvestmentPurchase_019ffbb6-9f65-7547-ab13-4a043f39e0fb" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_019ffbb6-9f65-7934-b271-7e5a7bda3ba0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_LineOfCredit_019ffbb6-9f65-7934-b271-7e5a7bda3ba0" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesPayable_019ffbb6-9f65-7ad9-aac4-8185bed2e370" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotesPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_NotesPayable_019ffbb6-9f65-7ad9-aac4-8185bed2e370" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019ffbb6-9f65-7254-bf87-b4871dc36118" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_019ffbb6-9f65-7d1b-bb8a-66237cdbcf9c" xlink:to="loc_us-gaap_Liabilities_019ffbb6-9f65-7254-bf87-b4871dc36118" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_019ffbb6-9f65-7f36-b448-67c4473ec2ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7318-a283-ebdee38a934b" xlink:to="loc_us-gaap_CommitmentsAndContingencies_019ffbb6-9f65-7f36-b448-67c4473ec2ee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityAbstract_019ffbb6-9f65-712e-9499-7c8328863b04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7318-a283-ebdee38a934b" xlink:to="loc_us-gaap_StockholdersEquityAbstract_019ffbb6-9f65-712e-9499-7c8328863b04" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_019ffbb6-9f65-7379-a01f-8208ca8d3142" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019ffbb6-9f65-712e-9499-7c8328863b04" xlink:to="loc_us-gaap_CommonStockValue_019ffbb6-9f65-7379-a01f-8208ca8d3142" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_019ffbb6-9f65-7f5d-8213-394f80ec995d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019ffbb6-9f65-712e-9499-7c8328863b04" xlink:to="loc_us-gaap_AdditionalPaidInCapital_019ffbb6-9f65-7f5d-8213-394f80ec995d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019ffbb6-9f65-7fca-a4c1-b3f972a9c2ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019ffbb6-9f65-712e-9499-7c8328863b04" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019ffbb6-9f65-7fca-a4c1-b3f972a9c2ed" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019ffbb6-9f65-7c16-858e-d04c64ffa6b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019ffbb6-9f65-712e-9499-7c8328863b04" xlink:to="loc_us-gaap_StockholdersEquity_019ffbb6-9f65-7c16-858e-d04c64ffa6b1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_019ffbb6-9f65-7510-abc7-fbda852bc291" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7318-a283-ebdee38a934b" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_019ffbb6-9f65-7510-abc7-fbda852bc291" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetAssetValuePerShare_019ffbb6-9f65-74e1-83d0-07f20da8323a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetAssetValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7318-a283-ebdee38a934b" xlink:to="loc_us-gaap_NetAssetValuePerShare_019ffbb6-9f65-74e1-83d0-07f20da8323a" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:type="simple" xlink:href="bbdc-20260930.xsd#ConsolidatedBalanceSheetsParenthetical"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019ffbb6-9f65-76bf-add5-f228a41efa8d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_us-gaap_StatementTable_019ffbb6-9f65-76bf-add5-f228a41efa8d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7d63-941a-6ea0c1b299bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f65-76bf-add5-f228a41efa8d" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7d63-941a-6ea0c1b299bb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7d63-941a-6ea0c1b299bb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7d63-941a-6ea0c1b299bb" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7d63-941a-6ea0c1b299bb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7e20-8cae-3ff2f40946a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7d63-941a-6ea0c1b299bb" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7e20-8cae-3ff2f40946a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f65-75c5-b0a3-62e619124355" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentUnaffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7e20-8cae-3ff2f40946a6" xlink:to="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f65-75c5-b0a3-62e619124355" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f65-79e7-9795-223d06ca5556" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7e20-8cae-3ff2f40946a6" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f65-79e7-9795-223d06ca5556" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f65-7bf2-941d-83fc6c1e686f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7e20-8cae-3ff2f40946a6" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f65-7bf2-941d-83fc6c1e686f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f65-777e-b242-ef59e5e97b4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f65-76bf-add5-f228a41efa8d" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f65-777e-b242-ef59e5e97b4e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-777e-b242-ef59e5e97b4e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f65-777e-b242-ef59e5e97b4e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-777e-b242-ef59e5e97b4e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-7eaf-ae37-91f6bec4b709" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f65-777e-b242-ef59e5e97b4e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-7eaf-ae37-91f6bec4b709" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f65-76d9-8822-6e757c38ce0b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f65-7eaf-ae37-91f6bec4b709" xlink:to="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f65-76d9-8822-6e757c38ce0b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-9f65-7b60-ae99-eebd8cd6ac13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-9f65-7b60-ae99-eebd8cd6ac13" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalents_019ffbb6-9f65-75f1-b033-cb0388ac1e91" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalents_019ffbb6-9f65-75f1-b033-cb0388ac1e91" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashHeldInForeignCurrencyAcquisitionCost_019ffbb6-9f65-7983-9147-451e03576cb0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashHeldInForeignCurrencyAcquisitionCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_us-gaap_CashHeldInForeignCurrencyAcquisitionCost_019ffbb6-9f65-7983-9147-451e03576cb0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DerivateAssetCost_019ffbb6-9f65-7fcb-8a23-f64b55f6de5b" xlink:href="bbdc-20260930.xsd#bbdc_DerivateAssetCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_bbdc_DerivateAssetCost_019ffbb6-9f65-7fcb-8a23-f64b55f6de5b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_019ffbb6-9f65-76f5-b9b4-c66de87255c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_019ffbb6-9f65-76f5-b9b4-c66de87255c3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_019ffbb6-9f65-793e-a2a5-9d45954daf4d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_019ffbb6-9f65-793e-a2a5-9d45954daf4d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_019ffbb6-9f65-772e-8748-3d43cd915eb6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_us-gaap_CommonStockSharesIssued_019ffbb6-9f65-772e-8748-3d43cd915eb6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019ffbb6-9f65-7b70-8793-22ac3b1ad461" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7c7b-88f7-af9be2a741dd" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019ffbb6-9f65-7b70-8793-22ac3b1ad461" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedStatementsofOperations" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedStatementsofOperations"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedStatementsofOperations" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019ffbb6-9f65-76f2-90a6-a22ae6f5637e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_StatementTable_019ffbb6-9f65-76f2-90a6-a22ae6f5637e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7edf-9bc5-5ba103285d50" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f65-76f2-90a6-a22ae6f5637e" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7edf-9bc5-5ba103285d50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7edf-9bc5-5ba103285d50_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7edf-9bc5-5ba103285d50" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7edf-9bc5-5ba103285d50_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7bdc-9a6c-900a3fc4f8df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f65-7edf-9bc5-5ba103285d50" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7bdc-9a6c-900a3fc4f8df" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f65-72d0-bbf1-12c3f01b9056" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentUnaffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7bdc-9a6c-900a3fc4f8df" xlink:to="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f65-72d0-bbf1-12c3f01b9056" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f65-75fa-9974-900e2336c8e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7bdc-9a6c-900a3fc4f8df" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f65-75fa-9974-900e2336c8e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f65-744a-b7b5-27fa409d5f54" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f65-7bdc-9a6c-900a3fc4f8df" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f65-744a-b7b5-27fa409d5f54" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019ffbb6-9f65-7e40-a396-38f4427466a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f65-76f2-90a6-a22ae6f5637e" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019ffbb6-9f65-7e40-a396-38f4427466a1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ffbb6-9f65-7e40-a396-38f4427466a1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019ffbb6-9f65-7e40-a396-38f4427466a1" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ffbb6-9f65-7e40-a396-38f4427466a1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ffbb6-9f65-7b29-9cab-d7f7697be3b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019ffbb6-9f65-7e40-a396-38f4427466a1" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ffbb6-9f65-7b29-9cab-d7f7697be3b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashMember_019ffbb6-9f65-7a06-8b47-19911763c6e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019ffbb6-9f65-7b29-9cab-d7f7697be3b5" xlink:to="loc_us-gaap_CashMember_019ffbb6-9f65-7a06-8b47-19911763c6e0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_019ffbb6-9f65-78bc-93ab-9804efbaf57a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenuesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_RevenuesAbstract_019ffbb6-9f65-78bc-93ab-9804efbaf57a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperatingPaidInCash_019ffbb6-9f65-7f46-95a9-e25f260ffb52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeOperatingPaidInCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019ffbb6-9f65-78bc-93ab-9804efbaf57a" xlink:to="loc_us-gaap_InterestIncomeOperatingPaidInCash_019ffbb6-9f65-7f46-95a9-e25f260ffb52" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_019ffbb6-9f65-7ab7-92cd-1b63c8e00e73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019ffbb6-9f65-78bc-93ab-9804efbaf57a" xlink:to="loc_us-gaap_DividendIncomeOperating_019ffbb6-9f65-7ab7-92cd-1b63c8e00e73" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FeeAndOtherIncome_019ffbb6-9f65-737c-80f5-7c73429aeb4f" xlink:href="bbdc-20260930.xsd#bbdc_FeeAndOtherIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019ffbb6-9f65-78bc-93ab-9804efbaf57a" xlink:to="loc_bbdc_FeeAndOtherIncome_019ffbb6-9f65-737c-80f5-7c73429aeb4f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperatingPaidInKind_019ffbb6-9f65-7874-83ec-50aed9a6c263" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeOperatingPaidInKind"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019ffbb6-9f65-78bc-93ab-9804efbaf57a" xlink:to="loc_us-gaap_InterestIncomeOperatingPaidInKind_019ffbb6-9f65-7874-83ec-50aed9a6c263" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperating_019ffbb6-9f65-7fb9-8187-6471199984a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019ffbb6-9f65-78bc-93ab-9804efbaf57a" xlink:to="loc_us-gaap_InterestIncomeOperating_019ffbb6-9f65-7fb9-8187-6471199984a4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossInvestmentIncomeOperating_019ffbb6-9f65-7fd6-8167-d4c7c2195e66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossInvestmentIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019ffbb6-9f65-78bc-93ab-9804efbaf57a" xlink:to="loc_us-gaap_GrossInvestmentIncomeOperating_019ffbb6-9f65-7fd6-8167-d4c7c2195e66" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpensesAbstract_019ffbb6-9f65-7489-8022-9b0cfb915f42" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_OperatingExpensesAbstract_019ffbb6-9f65-7489-8022-9b0cfb915f42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOperating_019ffbb6-9f65-7a51-8e6d-eaaec2d40c4a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019ffbb6-9f65-7489-8022-9b0cfb915f42" xlink:to="loc_us-gaap_InterestExpenseOperating_019ffbb6-9f65-7a51-8e6d-eaaec2d40c4a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeeExpense_019ffbb6-9f65-7c3b-97da-a7c65103b150" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementFeeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019ffbb6-9f65-7489-8022-9b0cfb915f42" xlink:to="loc_us-gaap_ManagementFeeExpense_019ffbb6-9f65-7c3b-97da-a7c65103b150" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncentiveFeeExpense_019ffbb6-9f65-719a-8867-535843685679" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncentiveFeeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019ffbb6-9f65-7489-8022-9b0cfb915f42" xlink:to="loc_us-gaap_IncentiveFeeExpense_019ffbb6-9f65-719a-8867-535843685679" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019ffbb6-9f65-77f8-889b-fd2a5ca5e3d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019ffbb6-9f65-7489-8022-9b0cfb915f42" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019ffbb6-9f65-77f8-889b-fd2a5ca5e3d8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInvestmentExpense_019ffbb6-9f65-7525-afb3-bc522aa7ac81" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeInvestmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019ffbb6-9f65-7489-8022-9b0cfb915f42" xlink:to="loc_us-gaap_InvestmentIncomeInvestmentExpense_019ffbb6-9f65-7525-afb3-bc522aa7ac81" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentIncome_019ffbb6-9f65-7869-8019-29a95a51bb85" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetInvestmentIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_NetInvestmentIncome_019ffbb6-9f65-7869-8019-29a95a51bb85" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeOperatingTaxExpenseBenefit_019ffbb6-9f65-7a06-8d7a-7e453465ef0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeOperatingTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_InvestmentIncomeOperatingTaxExpenseBenefit_019ffbb6-9f65-7a06-8d7a-7e453465ef0d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeOperatingAfterExpenseAndTax_019ffbb6-9f65-7735-a61e-9ff9e08a692c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeOperatingAfterExpenseAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_InvestmentIncomeOperatingAfterExpenseAndTax_019ffbb6-9f65-7735-a61e-9ff9e08a692c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NetRealizedGainsLossesAbstract_019ffbb6-9f65-7516-b4be-5a2e2046a167" xlink:href="bbdc-20260930.xsd#bbdc_NetRealizedGainsLossesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_bbdc_NetRealizedGainsLossesAbstract_019ffbb6-9f65-7516-b4be-5a2e2046a167" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtAndEquitySecuritiesRealizedGainLossBeforeDistributions_019ffbb6-9f65-73da-8899-e96bb507ce00" xlink:href="bbdc-20260930.xsd#bbdc_DebtAndEquitySecuritiesRealizedGainLossBeforeDistributions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_NetRealizedGainsLossesAbstract_019ffbb6-9f65-7516-b4be-5a2e2046a167" xlink:to="loc_bbdc_DebtAndEquitySecuritiesRealizedGainLossBeforeDistributions_019ffbb6-9f65-73da-8899-e96bb507ce00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RealizedGainLossOnCreditSupportAgreement_019ffbb6-9f65-7760-8a57-56d6d87dfcc9" xlink:href="bbdc-20260930.xsd#bbdc_RealizedGainLossOnCreditSupportAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_NetRealizedGainsLossesAbstract_019ffbb6-9f65-7516-b4be-5a2e2046a167" xlink:to="loc_bbdc_RealizedGainLossOnCreditSupportAgreement_019ffbb6-9f65-7760-8a57-56d6d87dfcc9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossRealized_019ffbb6-9f65-7a00-8b06-138d32dcfab9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyTransactionGainLossRealized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_NetRealizedGainsLossesAbstract_019ffbb6-9f65-7516-b4be-5a2e2046a167" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossRealized_019ffbb6-9f65-7a00-8b06-138d32dcfab9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfDerivatives_019ffbb6-9f65-72d4-af5a-7c0a7a90b602" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnSaleOfDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_NetRealizedGainsLossesAbstract_019ffbb6-9f65-7516-b4be-5a2e2046a167" xlink:to="loc_us-gaap_GainLossOnSaleOfDerivatives_019ffbb6-9f65-72d4-af5a-7c0a7a90b602" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f65-7627-8c35-40ecb4251785" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_NetRealizedGainsLossesAbstract_019ffbb6-9f65-7516-b4be-5a2e2046a167" xlink:to="loc_us-gaap_RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f65-7627-8c35-40ecb4251785" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedRecognizedUnrealizedAppreciationDepreciationNetAbstract_019ffbb6-9f65-779f-9bc1-2e4e4617defb" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedRecognizedUnrealizedAppreciationDepreciationNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_bbdc_InvestmentOwnedRecognizedUnrealizedAppreciationDepreciationNetAbstract_019ffbb6-9f65-779f-9bc1-2e4e4617defb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_019ffbb6-9f65-7fe0-add1-ad7b0b322895" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_InvestmentOwnedRecognizedUnrealizedAppreciationDepreciationNetAbstract_019ffbb6-9f65-779f-9bc1-2e4e4617defb" xlink:to="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss_019ffbb6-9f65-7fe0-add1-ad7b0b322895" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_UnrealizedGainLossOnCreditSupportAgreement_019ffbb6-9f65-7285-ab21-a4d071fc09ce" xlink:href="bbdc-20260930.xsd#bbdc_UnrealizedGainLossOnCreditSupportAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_InvestmentOwnedRecognizedUnrealizedAppreciationDepreciationNetAbstract_019ffbb6-9f65-779f-9bc1-2e4e4617defb" xlink:to="loc_bbdc_UnrealizedGainLossOnCreditSupportAgreement_019ffbb6-9f65-7285-ab21-a4d071fc09ce" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossUnrealized_019ffbb6-9f65-7d32-bef3-fe9b660c9eb4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyTransactionGainLossUnrealized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_InvestmentOwnedRecognizedUnrealizedAppreciationDepreciationNetAbstract_019ffbb6-9f65-779f-9bc1-2e4e4617defb" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossUnrealized_019ffbb6-9f65-7d32-bef3-fe9b660c9eb4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ffbb6-9f65-7668-8aa3-9c7fc7656238" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_InvestmentOwnedRecognizedUnrealizedAppreciationDepreciationNetAbstract_019ffbb6-9f65-779f-9bc1-2e4e4617defb" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ffbb6-9f65-7668-8aa3-9c7fc7656238" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f65-7c60-8b5f-e893f4404a66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_InvestmentOwnedRecognizedUnrealizedAppreciationDepreciationNetAbstract_019ffbb6-9f65-779f-9bc1-2e4e4617defb" xlink:to="loc_us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f65-7c60-8b5f-e893f4404a66" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f65-75cd-89d5-9f9992561b88" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f65-75cd-89d5-9f9992561b88" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax_019ffbb6-9f65-77ac-ab4c-6d4706f24747" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax_019ffbb6-9f65-77ac-ab4c-6d4706f24747" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_019ffbb6-9f65-7085-a7a8-3efb0ed95737" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_EarningsPerShareBasic_019ffbb6-9f65-7085-a7a8-3efb0ed95737" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_019ffbb6-9f65-7be8-8d6e-e968681f2213" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_EarningsPerShareDiluted_019ffbb6-9f65-7be8-8d6e-e968681f2213" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNetAssetValuePerSharePeriodIncreaseDecrease_019ffbb6-9f65-7fbc-9e3c-91e5e38fc626" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNetAssetValuePerSharePeriodIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_InvestmentCompanyNetAssetValuePerSharePeriodIncreaseDecrease_019ffbb6-9f65-7fbc-9e3c-91e5e38fc626" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareAbstract_019ffbb6-9f65-7961-9b2a-98bf3817ec72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_EarningsPerShareAbstract_019ffbb6-9f65-7961-9b2a-98bf3817ec72" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CommonStockDividendsPerShareDeclaredOrdinary_019ffbb6-9f65-77b9-b0e6-805f0e89dc67" xlink:href="bbdc-20260930.xsd#bbdc_CommonStockDividendsPerShareDeclaredOrdinary"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_019ffbb6-9f65-7961-9b2a-98bf3817ec72" xlink:to="loc_bbdc_CommonStockDividendsPerShareDeclaredOrdinary_019ffbb6-9f65-77b9-b0e6-805f0e89dc67" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CommonStockDividendsPerSharePaidOrdinary_019ffbb6-9f65-789e-8f2c-2af9fd92247a" xlink:href="bbdc-20260930.xsd#bbdc_CommonStockDividendsPerSharePaidOrdinary"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_019ffbb6-9f65-7961-9b2a-98bf3817ec72" xlink:to="loc_bbdc_CommonStockDividendsPerSharePaidOrdinary_019ffbb6-9f65-789e-8f2c-2af9fd92247a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CommonStockDividendsPerShareDeclaredSpecial_019ffbb6-9f65-7694-b536-827716ccae12" xlink:href="bbdc-20260930.xsd#bbdc_CommonStockDividendsPerShareDeclaredSpecial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_019ffbb6-9f65-7961-9b2a-98bf3817ec72" xlink:to="loc_bbdc_CommonStockDividendsPerShareDeclaredSpecial_019ffbb6-9f65-7694-b536-827716ccae12" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CommonStockDividendsPerSharePaidSpecial_019ffbb6-9f65-72b2-8b42-7bcf031709db" xlink:href="bbdc-20260930.xsd#bbdc_CommonStockDividendsPerSharePaidSpecial"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_019ffbb6-9f65-7961-9b2a-98bf3817ec72" xlink:to="loc_bbdc_CommonStockDividendsPerSharePaidSpecial_019ffbb6-9f65-72b2-8b42-7bcf031709db" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_019ffbb6-9f65-7664-af83-a87857898c8c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockDividendsPerShareDeclared"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_019ffbb6-9f65-7961-9b2a-98bf3817ec72" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_019ffbb6-9f65-7664-af83-a87857898c8c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareCashPaid_019ffbb6-9f65-791f-a96d-3aeb446ecd4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockDividendsPerShareCashPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_019ffbb6-9f65-7961-9b2a-98bf3817ec72" xlink:to="loc_us-gaap_CommonStockDividendsPerShareCashPaid_019ffbb6-9f65-791f-a96d-3aeb446ecd4e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019ffbb6-9f65-7736-af6b-f562dab7ba2a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019ffbb6-9f65-7736-af6b-f562dab7ba2a" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019ffbb6-9f65-7ae3-b0a2-0305384dc233" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f65-7045-bd46-8f7211413ed3" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019ffbb6-9f65-7ae3-b0a2-0305384dc233" xlink:type="arc" order="14"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedStatementsofChangesinNetAssets" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedStatementsofChangesinNetAssets"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedStatementsofChangesinNetAssets" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7d21-8bd2-7684d63a0b21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019ffbb6-9f66-741c-bff6-1fbf045369ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7d21-8bd2-7684d63a0b21" xlink:to="loc_us-gaap_StatementTable_019ffbb6-9f66-741c-bff6-1fbf045369ae" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019ffbb6-9f66-7846-bd45-c3ce8963b4a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f66-741c-bff6-1fbf045369ae" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019ffbb6-9f66-7846-bd45-c3ce8963b4a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019ffbb6-9f66-7846-bd45-c3ce8963b4a8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019ffbb6-9f66-7846-bd45-c3ce8963b4a8" xlink:to="loc_us-gaap_EquityComponentDomain_019ffbb6-9f66-7846-bd45-c3ce8963b4a8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019ffbb6-9f66-7aa3-8a29-a1c544c5bf1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019ffbb6-9f66-7846-bd45-c3ce8963b4a8" xlink:to="loc_us-gaap_EquityComponentDomain_019ffbb6-9f66-7aa3-8a29-a1c544c5bf1d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019ffbb6-9f66-706a-b8b8-234b03261ff2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019ffbb6-9f66-7aa3-8a29-a1c544c5bf1d" xlink:to="loc_us-gaap_CommonStockMember_019ffbb6-9f66-706a-b8b8-234b03261ff2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019ffbb6-9f66-79f2-9039-4fb939a5cacc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019ffbb6-9f66-7aa3-8a29-a1c544c5bf1d" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019ffbb6-9f66-79f2-9039-4fb939a5cacc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019ffbb6-9f66-7280-8d6c-3a56bbe2c764" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019ffbb6-9f66-7aa3-8a29-a1c544c5bf1d" xlink:to="loc_us-gaap_RetainedEarningsMember_019ffbb6-9f66-7280-8d6c-3a56bbe2c764" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNetAssetsRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7d21-8bd2-7684d63a0b21" xlink:to="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019ffbb6-9f66-7937-8022-09bbcaa894f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019ffbb6-9f66-7937-8022-09bbcaa894f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019ffbb6-9f66-7381-a693-88c70c2a37ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_us-gaap_StockholdersEquity_019ffbb6-9f66-7381-a693-88c70c2a37ee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeOperatingAfterExpenseAndTax_019ffbb6-9f66-764c-8449-bd26bf15a8a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeOperatingAfterExpenseAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_us-gaap_InvestmentIncomeOperatingAfterExpenseAndTax_019ffbb6-9f66-764c-8449-bd26bf15a8a7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f66-7bbf-8351-7ba5857cde01" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_us-gaap_RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f66-7bbf-8351-7ba5857cde01" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f66-7336-b3f3-529f14ff67fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_us-gaap_UnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingBeforeTax_019ffbb6-9f66-7336-b3f3-529f14ff67fa" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyDividendDistribution_019ffbb6-9f66-7d81-be7e-2a1c143d6df1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyDividendDistribution"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_us-gaap_InvestmentCompanyDividendDistribution_019ffbb6-9f66-7d81-be7e-2a1c143d6df1" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AdjustmentsToAdditionalPaidInCapitalDeemedContributionFromCreditSupportAgreement_019ffbb6-9f66-7689-96f4-343967709af3" xlink:href="bbdc-20260930.xsd#bbdc_AdjustmentsToAdditionalPaidInCapitalDeemedContributionFromCreditSupportAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_bbdc_AdjustmentsToAdditionalPaidInCapitalDeemedContributionFromCreditSupportAgreement_019ffbb6-9f66-7689-96f4-343967709af3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_01a0a8be-21d9-75fb-a603-95d499a147ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_01a0a8be-21d9-75fb-a603-95d499a147ee" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_01a0a8be-21d9-7bcc-bfb6-b46088bb6546" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNetAssetsRollForward_019ffbb6-9f66-789a-9fbd-b20074a2fd5f" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_01a0a8be-21d9-7bcc-bfb6-b46088bb6546" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019ffbb6-9f66-70c7-af79-9cb567322e7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019ffbb6-9f66-7f76-a1a0-154aa983825a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestments" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestments"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestments" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-9f66-7d9f-8158-8407ed4b0833" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-9f66-7d9f-8158-8407ed4b0833" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-7376-9855-0c3ecf5b1475" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-7376-9855-0c3ecf5b1475" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7376-9855-0c3ecf5b1475_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-7376-9855-0c3ecf5b1475" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7376-9855-0c3ecf5b1475_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-7376-9855-0c3ecf5b1475" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f66-770b-83a3-ec7a3062a9e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentUnaffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:to="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f66-770b-83a3-ec7a3062a9e1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f66-7c3a-a856-9a768a22b344" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f66-7c3a-a856-9a768a22b344" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f66-74b6-a0c4-8d35c208419d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f66-74b6-a0c4-8d35c208419d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-9f66-76cc-bcdb-4be2902b5037" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesByIndustryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-9f66-76cc-bcdb-4be2902b5037" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-76cc-bcdb-4be2902b5037_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-9f66-76cc-bcdb-4be2902b5037" xlink:to="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-76cc-bcdb-4be2902b5037_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-9f66-76cc-bcdb-4be2902b5037" xlink:to="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AerospaceSectorMember_019ffbb6-9f66-7373-bb80-6a3779118cff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AerospaceSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_AerospaceSectorMember_019ffbb6-9f66-7373-bb80-6a3779118cff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AutomotiveSectorMember_019ffbb6-9f66-7eef-89c8-855c3adaec52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AutomotiveSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_AutomotiveSectorMember_019ffbb6-9f66-7eef-89c8-855c3adaec52" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BankingFinanceInsuranceAndRealEstateMember_019ffbb6-9f66-7602-8bab-363baa89357d" xlink:href="bbdc-20260930.xsd#bbdc_BankingFinanceInsuranceAndRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_BankingFinanceInsuranceAndRealEstateMember_019ffbb6-9f66-7602-8bab-363baa89357d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BeverageFoodAndTobaccoMember_019ffbb6-9f66-7f29-9340-d285055e352b" xlink:href="bbdc-20260930.xsd#bbdc_BeverageFoodAndTobaccoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_BeverageFoodAndTobaccoMember_019ffbb6-9f66-7f29-9340-d285055e352b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CapitalEquipmentMember_019ffbb6-9f66-75ed-a04d-43c5e35c3690" xlink:href="bbdc-20260930.xsd#bbdc_CapitalEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_CapitalEquipmentMember_019ffbb6-9f66-75ed-a04d-43c5e35c3690" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ChemicalsSectorMember_019ffbb6-9f66-7d2a-a958-fc6566b93379" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ChemicalsSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_ChemicalsSectorMember_019ffbb6-9f66-7d2a-a958-fc6566b93379" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConstructionSectorMember_019ffbb6-9f66-7637-9351-9b683671523b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConstructionSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_ConstructionSectorMember_019ffbb6-9f66-7637-9351-9b683671523b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ConsumerGoodsDurableMember_019ffbb6-9f66-7c4d-977c-9f5ce9248f9c" xlink:href="bbdc-20260930.xsd#bbdc_ConsumerGoodsDurableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_ConsumerGoodsDurableMember_019ffbb6-9f66-7c4d-977c-9f5ce9248f9c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ConsumerGoodsNonDurableMember_019ffbb6-9f66-7f91-b2f4-c9cb6a38261b" xlink:href="bbdc-20260930.xsd#bbdc_ConsumerGoodsNonDurableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_ConsumerGoodsNonDurableMember_019ffbb6-9f66-7f91-b2f4-c9cb6a38261b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContainerAndPackagingSectorMember_019ffbb6-9f66-7300-9cd9-27cdee2f3e83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContainerAndPackagingSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_ContainerAndPackagingSectorMember_019ffbb6-9f66-7300-9cd9-27cdee2f3e83" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnergyElectricityMember_019ffbb6-9f66-744c-b1c0-ca1cf59c9666" xlink:href="bbdc-20260930.xsd#bbdc_EnergyElectricityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_EnergyElectricityMember_019ffbb6-9f66-744c-b1c0-ca1cf59c9666" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnergyOilAndGasMember_019ffbb6-9f66-7f57-82c2-01f9a252756a" xlink:href="bbdc-20260930.xsd#bbdc_EnergyOilAndGasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_EnergyOilAndGasMember_019ffbb6-9f66-7f57-82c2-01f9a252756a" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnvironmentalIndustriesMember_019ffbb6-9f66-74fe-9701-af3dac355dc7" xlink:href="bbdc-20260930.xsd#bbdc_EnvironmentalIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_EnvironmentalIndustriesMember_019ffbb6-9f66-74fe-9701-af3dac355dc7" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HealthcareAndPharmaceuticalsMember_019ffbb6-9f66-7d07-8314-e2a917a00006" xlink:href="bbdc-20260930.xsd#bbdc_HealthcareAndPharmaceuticalsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_HealthcareAndPharmaceuticalsMember_019ffbb6-9f66-7d07-8314-e2a917a00006" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HighTechIndustriesMember_019ffbb6-9f66-75e2-9340-318c2fa282ba" xlink:href="bbdc-20260930.xsd#bbdc_HighTechIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_HighTechIndustriesMember_019ffbb6-9f66-75e2-9340-318c2fa282ba" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HotelGamingAndLeisureMember_019ffbb6-9f66-7eb2-8c8b-a9fa2e121d24" xlink:href="bbdc-20260930.xsd#bbdc_HotelGamingAndLeisureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_HotelGamingAndLeisureMember_019ffbb6-9f66-7eb2-8c8b-a9fa2e121d24" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentFundsAndVehiclesMember_019ffbb6-9f66-76e2-94f5-05ad27db7885" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentFundsAndVehiclesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_InvestmentFundsAndVehiclesMember_019ffbb6-9f66-76e2-94f5-05ad27db7885" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaAdvertisingPrintingAndPublishingMember_019ffbb6-9f66-7d60-909c-f9e8885b4533" xlink:href="bbdc-20260930.xsd#bbdc_MediaAdvertisingPrintingAndPublishingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_MediaAdvertisingPrintingAndPublishingMember_019ffbb6-9f66-7d60-909c-f9e8885b4533" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaBroadcastingAndSubscriptionMember_019ffbb6-9f66-7092-af3c-a38cfd7330d2" xlink:href="bbdc-20260930.xsd#bbdc_MediaBroadcastingAndSubscriptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_MediaBroadcastingAndSubscriptionMember_019ffbb6-9f66-7092-af3c-a38cfd7330d2" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaDiversifiedAndProductionMember_019ffbb6-9f66-7e20-867c-98213e692bae" xlink:href="bbdc-20260930.xsd#bbdc_MediaDiversifiedAndProductionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_MediaDiversifiedAndProductionMember_019ffbb6-9f66-7e20-867c-98213e692bae" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MetalsAndMiningMember_019ffbb6-9f66-7c76-be83-5565494b4139" xlink:href="bbdc-20260930.xsd#bbdc_MetalsAndMiningMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_MetalsAndMiningMember_019ffbb6-9f66-7c76-be83-5565494b4139" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ServicesBusinessMember_019ffbb6-9f66-7a35-8db3-525a1829e96a" xlink:href="bbdc-20260930.xsd#bbdc_ServicesBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_ServicesBusinessMember_019ffbb6-9f66-7a35-8db3-525a1829e96a" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ServicesConsumerMember_019ffbb6-9f66-70a6-a827-3695a8aa116c" xlink:href="bbdc-20260930.xsd#bbdc_ServicesConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_ServicesConsumerMember_019ffbb6-9f66-70a6-a827-3695a8aa116c" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_StructuredProductsMember_019ffbb6-9f66-7f93-9187-3f88dad2ac87" xlink:href="bbdc-20260930.xsd#bbdc_StructuredProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_StructuredProductsMember_019ffbb6-9f66-7f93-9187-3f88dad2ac87" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TelecommunicationsMember_019ffbb6-9f66-7095-9099-4d8ae4f993e8" xlink:href="bbdc-20260930.xsd#bbdc_TelecommunicationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_TelecommunicationsMember_019ffbb6-9f66-7095-9099-4d8ae4f993e8" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TransportationCargoMember_019ffbb6-9f66-78dc-bc97-7d9417e8b67c" xlink:href="bbdc-20260930.xsd#bbdc_TransportationCargoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_TransportationCargoMember_019ffbb6-9f66-78dc-bc97-7d9417e8b67c" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TransportationConsumerMember_019ffbb6-9f66-76d5-8d9b-864bb8a045f4" xlink:href="bbdc-20260930.xsd#bbdc_TransportationConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_TransportationConsumerMember_019ffbb6-9f66-76d5-8d9b-864bb8a045f4" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_UtilitiesElectricMember_019ffbb6-9f66-7d5b-9fdf-c2a8c1d0e296" xlink:href="bbdc-20260930.xsd#bbdc_UtilitiesElectricMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_UtilitiesElectricMember_019ffbb6-9f66-7d5b-9fdf-c2a8c1d0e296" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesMember_019ffbb6-9f66-7581-9f42-e7e9b9cff9b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:to="loc_us-gaap_DebtSecuritiesMember_019ffbb6-9f66-7581-9f42-e7e9b9cff9b0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_019ffbb6-9f66-7e56-a177-f8f750037e7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:to="loc_us-gaap_EquitySecuritiesMember_019ffbb6-9f66-7e56-a177-f8f750037e7a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RoyaltyMember_019ffbb6-9f66-7f42-bea1-498c92733db5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RoyaltyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:to="loc_us-gaap_RoyaltyMember_019ffbb6-9f66-7f42-bea1-498c92733db5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-7b0d-8e11-77d127f3eeed" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-7b0d-8e11-77d127f3eeed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-7f95-998f-74f693946b81" xlink:href="bbdc-20260930.xsd#bbdc_SierraSeniorLoanStrategyJVILLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:to="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-7f95-998f-74f693946b81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7c06-9e2e-9e845e9bfc15" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7c06-9e2e-9e845e9bfc15" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-77a4-990a-ec44bd53f1d0" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-77a4-990a-ec44bd53f1d0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedBalanceShares_019ffbb6-9f66-73c3-b630-206b700296c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedBalanceShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedBalanceShares_019ffbb6-9f66-73c3-b630-206b700296c9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentBasisSpreadVariableRate_019ffbb6-9f66-701f-b059-f8f3d8ff35aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentBasisSpreadVariableRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentBasisSpreadVariableRate_019ffbb6-9f66-701f-b059-f8f3d8ff35aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRate_019ffbb6-9f66-7924-a4ba-1452eaf6dcaf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentInterestRate_019ffbb6-9f66-7924-a4ba-1452eaf6dcaf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRatePaidInKind_019ffbb6-9f66-78af-a94f-6b6cf35b95e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRatePaidInKind"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentInterestRatePaidInKind_019ffbb6-9f66-78af-a94f-6b6cf35b95e2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentInterestRatePaidInKindToggleOne_019ffbb6-9f66-70ed-b312-caa4d9bae485" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentInterestRatePaidInKindToggleOne"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_bbdc_InvestmentInterestRatePaidInKindToggleOne_019ffbb6-9f66-70ed-b312-caa4d9bae485" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedBalancePrincipalAmount_019ffbb6-9f66-71e6-986a-161488867200" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedBalancePrincipalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedBalancePrincipalAmount_019ffbb6-9f66-71e6-986a-161488867200" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-9f66-76a0-8cfd-31129d3178c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-9f66-76a0-8cfd-31129d3178c2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-9f66-7a58-a715-9b9452362ad2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-9f66-7a58-a715-9b9452362ad2" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019ffbb6-9f66-714f-89d1-0bfb0f5a9b2b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedPercentOfNetAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019ffbb6-9f66-714f-89d1-0bfb0f5a9b2b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedInterestCurrentYield_019ffbb6-9f66-7352-8808-d85c351e9456" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedInterestCurrentYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_bbdc_InvestmentOwnedInterestCurrentYield_019ffbb6-9f66-7352-8808-d85c351e9456" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019ffbb6-9f66-7487-b1d4-5ef1d51ca1a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019ffbb6-9f66-7487-b1d4-5ef1d51ca1a5" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestments_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestments_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestments_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-7376-9855-0c3ecf5b1475" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-7376-9855-0c3ecf5b1475" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7376-9855-0c3ecf5b1475_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-7376-9855-0c3ecf5b1475" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7376-9855-0c3ecf5b1475_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-7376-9855-0c3ecf5b1475" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f66-770b-83a3-ec7a3062a9e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentUnaffiliatedIssuerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:to="loc_us-gaap_InvestmentUnaffiliatedIssuerMember_019ffbb6-9f66-770b-83a3-ec7a3062a9e1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f66-7c3a-a856-9a768a22b344" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f66-7c3a-a856-9a768a22b344" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f66-74b6-a0c4-8d35c208419d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-778a-847d-b5a8dad5c8cd" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f66-74b6-a0c4-8d35c208419d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-9f66-76cc-bcdb-4be2902b5037" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesByIndustryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-9f66-76cc-bcdb-4be2902b5037" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-76cc-bcdb-4be2902b5037_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-9f66-76cc-bcdb-4be2902b5037" xlink:to="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-76cc-bcdb-4be2902b5037_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-9f66-76cc-bcdb-4be2902b5037" xlink:to="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AerospaceSectorMember_019ffbb6-9f66-7373-bb80-6a3779118cff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AerospaceSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_AerospaceSectorMember_019ffbb6-9f66-7373-bb80-6a3779118cff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AutomotiveSectorMember_019ffbb6-9f66-7eef-89c8-855c3adaec52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AutomotiveSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_AutomotiveSectorMember_019ffbb6-9f66-7eef-89c8-855c3adaec52" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BankingFinanceInsuranceAndRealEstateMember_019ffbb6-9f66-7602-8bab-363baa89357d" xlink:href="bbdc-20260930.xsd#bbdc_BankingFinanceInsuranceAndRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_BankingFinanceInsuranceAndRealEstateMember_019ffbb6-9f66-7602-8bab-363baa89357d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BeverageFoodAndTobaccoMember_019ffbb6-9f66-7f29-9340-d285055e352b" xlink:href="bbdc-20260930.xsd#bbdc_BeverageFoodAndTobaccoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_BeverageFoodAndTobaccoMember_019ffbb6-9f66-7f29-9340-d285055e352b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CapitalEquipmentMember_019ffbb6-9f66-75ed-a04d-43c5e35c3690" xlink:href="bbdc-20260930.xsd#bbdc_CapitalEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_CapitalEquipmentMember_019ffbb6-9f66-75ed-a04d-43c5e35c3690" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ChemicalsSectorMember_019ffbb6-9f66-7d2a-a958-fc6566b93379" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ChemicalsSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_ChemicalsSectorMember_019ffbb6-9f66-7d2a-a958-fc6566b93379" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConstructionSectorMember_019ffbb6-9f66-7637-9351-9b683671523b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConstructionSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_ConstructionSectorMember_019ffbb6-9f66-7637-9351-9b683671523b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ConsumerGoodsDurableMember_019ffbb6-9f66-7c4d-977c-9f5ce9248f9c" xlink:href="bbdc-20260930.xsd#bbdc_ConsumerGoodsDurableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_ConsumerGoodsDurableMember_019ffbb6-9f66-7c4d-977c-9f5ce9248f9c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ConsumerGoodsNonDurableMember_019ffbb6-9f66-7f91-b2f4-c9cb6a38261b" xlink:href="bbdc-20260930.xsd#bbdc_ConsumerGoodsNonDurableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_ConsumerGoodsNonDurableMember_019ffbb6-9f66-7f91-b2f4-c9cb6a38261b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContainerAndPackagingSectorMember_019ffbb6-9f66-7300-9cd9-27cdee2f3e83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContainerAndPackagingSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_us-gaap_ContainerAndPackagingSectorMember_019ffbb6-9f66-7300-9cd9-27cdee2f3e83" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnergyElectricityMember_019ffbb6-9f66-744c-b1c0-ca1cf59c9666" xlink:href="bbdc-20260930.xsd#bbdc_EnergyElectricityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_EnergyElectricityMember_019ffbb6-9f66-744c-b1c0-ca1cf59c9666" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnergyOilAndGasMember_019ffbb6-9f66-7f57-82c2-01f9a252756a" xlink:href="bbdc-20260930.xsd#bbdc_EnergyOilAndGasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_EnergyOilAndGasMember_019ffbb6-9f66-7f57-82c2-01f9a252756a" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnvironmentalIndustriesMember_019ffbb6-9f66-74fe-9701-af3dac355dc7" xlink:href="bbdc-20260930.xsd#bbdc_EnvironmentalIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_EnvironmentalIndustriesMember_019ffbb6-9f66-74fe-9701-af3dac355dc7" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HealthcareAndPharmaceuticalsMember_019ffbb6-9f66-7d07-8314-e2a917a00006" xlink:href="bbdc-20260930.xsd#bbdc_HealthcareAndPharmaceuticalsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_HealthcareAndPharmaceuticalsMember_019ffbb6-9f66-7d07-8314-e2a917a00006" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HighTechIndustriesMember_019ffbb6-9f66-75e2-9340-318c2fa282ba" xlink:href="bbdc-20260930.xsd#bbdc_HighTechIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_HighTechIndustriesMember_019ffbb6-9f66-75e2-9340-318c2fa282ba" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HotelGamingAndLeisureMember_019ffbb6-9f66-7eb2-8c8b-a9fa2e121d24" xlink:href="bbdc-20260930.xsd#bbdc_HotelGamingAndLeisureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_HotelGamingAndLeisureMember_019ffbb6-9f66-7eb2-8c8b-a9fa2e121d24" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentFundsAndVehiclesMember_019ffbb6-9f66-76e2-94f5-05ad27db7885" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentFundsAndVehiclesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_InvestmentFundsAndVehiclesMember_019ffbb6-9f66-76e2-94f5-05ad27db7885" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaAdvertisingPrintingAndPublishingMember_019ffbb6-9f66-7d60-909c-f9e8885b4533" xlink:href="bbdc-20260930.xsd#bbdc_MediaAdvertisingPrintingAndPublishingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_MediaAdvertisingPrintingAndPublishingMember_019ffbb6-9f66-7d60-909c-f9e8885b4533" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaBroadcastingAndSubscriptionMember_019ffbb6-9f66-7092-af3c-a38cfd7330d2" xlink:href="bbdc-20260930.xsd#bbdc_MediaBroadcastingAndSubscriptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_MediaBroadcastingAndSubscriptionMember_019ffbb6-9f66-7092-af3c-a38cfd7330d2" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaDiversifiedAndProductionMember_019ffbb6-9f66-7e20-867c-98213e692bae" xlink:href="bbdc-20260930.xsd#bbdc_MediaDiversifiedAndProductionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_MediaDiversifiedAndProductionMember_019ffbb6-9f66-7e20-867c-98213e692bae" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MetalsAndMiningMember_019ffbb6-9f66-7c76-be83-5565494b4139" xlink:href="bbdc-20260930.xsd#bbdc_MetalsAndMiningMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_MetalsAndMiningMember_019ffbb6-9f66-7c76-be83-5565494b4139" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ServicesBusinessMember_019ffbb6-9f66-7a35-8db3-525a1829e96a" xlink:href="bbdc-20260930.xsd#bbdc_ServicesBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_ServicesBusinessMember_019ffbb6-9f66-7a35-8db3-525a1829e96a" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ServicesConsumerMember_019ffbb6-9f66-70a6-a827-3695a8aa116c" xlink:href="bbdc-20260930.xsd#bbdc_ServicesConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_ServicesConsumerMember_019ffbb6-9f66-70a6-a827-3695a8aa116c" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_StructuredProductsMember_019ffbb6-9f66-7f93-9187-3f88dad2ac87" xlink:href="bbdc-20260930.xsd#bbdc_StructuredProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_StructuredProductsMember_019ffbb6-9f66-7f93-9187-3f88dad2ac87" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TelecommunicationsMember_019ffbb6-9f66-7095-9099-4d8ae4f993e8" xlink:href="bbdc-20260930.xsd#bbdc_TelecommunicationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_TelecommunicationsMember_019ffbb6-9f66-7095-9099-4d8ae4f993e8" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TransportationCargoMember_019ffbb6-9f66-78dc-bc97-7d9417e8b67c" xlink:href="bbdc-20260930.xsd#bbdc_TransportationCargoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_TransportationCargoMember_019ffbb6-9f66-78dc-bc97-7d9417e8b67c" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TransportationConsumerMember_019ffbb6-9f66-76d5-8d9b-864bb8a045f4" xlink:href="bbdc-20260930.xsd#bbdc_TransportationConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_TransportationConsumerMember_019ffbb6-9f66-76d5-8d9b-864bb8a045f4" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_UtilitiesElectricMember_019ffbb6-9f66-7d5b-9fdf-c2a8c1d0e296" xlink:href="bbdc-20260930.xsd#bbdc_UtilitiesElectricMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-9f66-7c46-a287-caf83972fdbf" xlink:to="loc_bbdc_UtilitiesElectricMember_019ffbb6-9f66-7d5b-9fdf-c2a8c1d0e296" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-9f66-72c8-a7bb-2c2823c6bb6c" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesMember_019ffbb6-9f66-7581-9f42-e7e9b9cff9b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:to="loc_us-gaap_DebtSecuritiesMember_019ffbb6-9f66-7581-9f42-e7e9b9cff9b0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_019ffbb6-9f66-7e56-a177-f8f750037e7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:to="loc_us-gaap_EquitySecuritiesMember_019ffbb6-9f66-7e56-a177-f8f750037e7a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RoyaltyMember_019ffbb6-9f66-7f42-bea1-498c92733db5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RoyaltyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-9f66-7f37-8f0c-5b44c95c99f1" xlink:to="loc_us-gaap_RoyaltyMember_019ffbb6-9f66-7f42-bea1-498c92733db5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7879-a6a8-f7855f9985a4" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7e40-bef8-3fa03ef8a2ae" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-7b0d-8e11-77d127f3eeed" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-7b0d-8e11-77d127f3eeed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-7f95-998f-74f693946b81" xlink:href="bbdc-20260930.xsd#bbdc_SierraSeniorLoanStrategyJVILLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:to="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-7f95-998f-74f693946b81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7c06-9e2e-9e845e9bfc15" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7c06-9e2e-9e845e9bfc15" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-77a4-990a-ec44bd53f1d0" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7b5e-9a44-c4830f6717f3" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-77a4-990a-ec44bd53f1d0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedBalanceShares_019ffbb6-9f66-73c3-b630-206b700296c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedBalanceShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedBalanceShares_019ffbb6-9f66-73c3-b630-206b700296c9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentBasisSpreadVariableRate_019ffbb6-9f66-701f-b059-f8f3d8ff35aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentBasisSpreadVariableRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentBasisSpreadVariableRate_019ffbb6-9f66-701f-b059-f8f3d8ff35aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRate_019ffbb6-9f66-7924-a4ba-1452eaf6dcaf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentInterestRate_019ffbb6-9f66-7924-a4ba-1452eaf6dcaf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRatePaidInKind_019ffbb6-9f66-78af-a94f-6b6cf35b95e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRatePaidInKind"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentInterestRatePaidInKind_019ffbb6-9f66-78af-a94f-6b6cf35b95e2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentInterestRatePaidInKindToggleOne_019ffbb6-9f66-70ed-b312-caa4d9bae485" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentInterestRatePaidInKindToggleOne"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_bbdc_InvestmentInterestRatePaidInKindToggleOne_019ffbb6-9f66-70ed-b312-caa4d9bae485" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedBalancePrincipalAmount_019ffbb6-9f66-71e6-986a-161488867200" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedBalancePrincipalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedBalancePrincipalAmount_019ffbb6-9f66-71e6-986a-161488867200" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-9f66-76a0-8cfd-31129d3178c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-9f66-76a0-8cfd-31129d3178c2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-9f66-7a58-a715-9b9452362ad2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-9f66-7a58-a715-9b9452362ad2" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019ffbb6-9f66-714f-89d1-0bfb0f5a9b2b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedPercentOfNetAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019ffbb6-9f66-714f-89d1-0bfb0f5a9b2b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedInterestCurrentYield_019ffbb6-9f66-7352-8808-d85c351e9456" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedInterestCurrentYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_bbdc_InvestmentOwnedInterestCurrentYield_019ffbb6-9f66-7352-8808-d85c351e9456" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019ffbb6-9f66-7487-b1d4-5ef1d51ca1a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-76b4-b566-c4e332c7877f" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019ffbb6-9f66-7487-b1d4-5ef1d51ca1a5" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsDerivativeInstrumentsParenthetical" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestmentsDerivativeInstrumentsParenthetical"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsDerivativeInstrumentsParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-76bc-8fb8-1b524dac02e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-76bc-8fb8-1b524dac02e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_019ffbb6-9f66-7933-9f21-5fdce8cdd416" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-76bc-8fb8-1b524dac02e7" xlink:to="loc_us-gaap_InterestRateSwapMember_019ffbb6-9f66-7933-9f21-5fdce8cdd416" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f66-7494-a7a2-f30bc2ea9250" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-76bc-8fb8-1b524dac02e7" xlink:to="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f66-7494-a7a2-f30bc2ea9250" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-9f66-75df-862e-0362ddf10cc0" xlink:href="bbdc-20260930.xsd#bbdc_NewSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f66-7494-a7a2-f30bc2ea9250" xlink:to="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-9f66-75df-862e-0362ddf10cc0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-9f66-79fd-adbf-246bdba61b6e" xlink:href="bbdc-20260930.xsd#bbdc_PriorSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f66-7494-a7a2-f30bc2ea9250" xlink:to="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-9f66-79fd-adbf-246bdba61b6e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-9f66-745f-b79c-3745713f3aa2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-9f66-745f-b79c-3745713f3aa2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-745f-b79c-3745713f3aa2_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-9f66-745f-b79c-3745713f3aa2" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-745f-b79c-3745713f3aa2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-710e-bc05-895ce720f0da" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-9f66-745f-b79c-3745713f3aa2" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-710e-bc05-895ce720f0da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BaringsLLCMember_019ffbb6-9f66-7867-b8a5-22e00bbfa0b1" xlink:href="bbdc-20260930.xsd#bbdc_BaringsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-710e-bc05-895ce720f0da" xlink:to="loc_bbdc_BaringsLLCMember_019ffbb6-9f66-7867-b8a5-22e00bbfa0b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OpenSwapContractIdentifierAxis_019ffbb6-9f66-77ae-96e0-fd4482eed4d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OpenSwapContractIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:to="loc_us-gaap_OpenSwapContractIdentifierAxis_019ffbb6-9f66-77ae-96e0-fd4482eed4d8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFixedInterestRate_019ffbb6-9f66-7ccd-8f8e-87dfb16e458e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFixedInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeFixedInterestRate_019ffbb6-9f66-7ccd-8f8e-87dfb16e458e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeBasisSpreadOnVariableRate_019ffbb6-9f66-77c2-8e94-68c0a190b61c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeBasisSpreadOnVariableRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeBasisSpreadOnVariableRate_019ffbb6-9f66-77c2-8e94-68c0a190b61c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-9f66-7d11-9210-ea7556ac8b6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-9f66-7d11-9210-ea7556ac8b6a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019ffbb6-9f66-7dba-a912-d37be69418f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeLiabilities_019ffbb6-9f66-7dba-a912-d37be69418f4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ffbb6-9f66-766f-b62d-0f7c8b6cff89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ffbb6-9f66-766f-b62d-0f7c8b6cff89" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019ffbb6-9f66-74c9-8bd6-0a0089f06a94" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeAssets_019ffbb6-9f66-74c9-8bd6-0a0089f06a94" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsCurrent_019ffbb6-9f66-7903-8fa5-0bb785f2cc66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeAssetsCurrent_019ffbb6-9f66-7903-8fa5-0bb785f2cc66" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsDerivativeInstrumentsParenthetical_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestmentsDerivativeInstrumentsParenthetical_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsDerivativeInstrumentsParenthetical_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-76bc-8fb8-1b524dac02e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-9f66-7b3b-93ff-c1f3154b12d7" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-76bc-8fb8-1b524dac02e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_019ffbb6-9f66-7933-9f21-5fdce8cdd416" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-76bc-8fb8-1b524dac02e7" xlink:to="loc_us-gaap_InterestRateSwapMember_019ffbb6-9f66-7933-9f21-5fdce8cdd416" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f66-7494-a7a2-f30bc2ea9250" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditRiskContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-9f66-76bc-8fb8-1b524dac02e7" xlink:to="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f66-7494-a7a2-f30bc2ea9250" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-9f66-75df-862e-0362ddf10cc0" xlink:href="bbdc-20260930.xsd#bbdc_NewSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f66-7494-a7a2-f30bc2ea9250" xlink:to="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-9f66-75df-862e-0362ddf10cc0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-9f66-79fd-adbf-246bdba61b6e" xlink:href="bbdc-20260930.xsd#bbdc_PriorSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditRiskContractMember_019ffbb6-9f66-7494-a7a2-f30bc2ea9250" xlink:to="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-9f66-79fd-adbf-246bdba61b6e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-9f66-745f-b79c-3745713f3aa2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7b71-9a8d-99803cc456f9" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-9f66-745f-b79c-3745713f3aa2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-745f-b79c-3745713f3aa2_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-9f66-745f-b79c-3745713f3aa2" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-745f-b79c-3745713f3aa2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-710e-bc05-895ce720f0da" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-9f66-745f-b79c-3745713f3aa2" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-710e-bc05-895ce720f0da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BaringsLLCMember_019ffbb6-9f66-7867-b8a5-22e00bbfa0b1" xlink:href="bbdc-20260930.xsd#bbdc_BaringsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-9f66-710e-bc05-895ce720f0da" xlink:to="loc_bbdc_BaringsLLCMember_019ffbb6-9f66-7867-b8a5-22e00bbfa0b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFixedInterestRate_019ffbb6-9f66-7ccd-8f8e-87dfb16e458e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFixedInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeFixedInterestRate_019ffbb6-9f66-7ccd-8f8e-87dfb16e458e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeBasisSpreadOnVariableRate_019ffbb6-9f66-77c2-8e94-68c0a190b61c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeBasisSpreadOnVariableRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeBasisSpreadOnVariableRate_019ffbb6-9f66-77c2-8e94-68c0a190b61c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-9f66-7d11-9210-ea7556ac8b6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-9f66-7d11-9210-ea7556ac8b6a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019ffbb6-9f66-7dba-a912-d37be69418f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeLiabilities_019ffbb6-9f66-7dba-a912-d37be69418f4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ffbb6-9f66-766f-b62d-0f7c8b6cff89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ffbb6-9f66-766f-b62d-0f7c8b6cff89" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019ffbb6-9f66-74c9-8bd6-0a0089f06a94" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeAssets_019ffbb6-9f66-74c9-8bd6-0a0089f06a94" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsCurrent_019ffbb6-9f66-7903-8fa5-0bb785f2cc66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7b0e-81ce-148cf5eb9ef3" xlink:to="loc_us-gaap_DerivativeAssetsCurrent_019ffbb6-9f66-7903-8fa5-0bb785f2cc66" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsForeignCurrencyForwardContractsParenthetical" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestmentsForeignCurrencyForwardContractsParenthetical"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsForeignCurrencyForwardContractsParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7f39-906a-1f7ceeca9dc6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-74e7-8b7b-55231033065c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7f39-906a-1f7ceeca9dc6" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-74e7-8b7b-55231033065c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OpenForwardForeignCurrencyContractIdentifierAxis_019ffbb6-9f66-7241-9ebe-a417a076c24f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OpenForwardForeignCurrencyContractIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-74e7-8b7b-55231033065c" xlink:to="loc_us-gaap_OpenForwardForeignCurrencyContractIdentifierAxis_019ffbb6-9f66-7241-9ebe-a417a076c24f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyDerivativesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7f39-906a-1f7ceeca9dc6" xlink:to="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ffbb6-9f66-7188-9088-1e13623d87d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ffbb6-9f66-7188-9088-1e13623d87d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount_019ffbb6-9f66-7f34-832c-d7096bee4840" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeAssetNotionalAmount_019ffbb6-9f66-7f34-832c-d7096bee4840" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019ffbb6-9f66-757e-a5b0-71681180fa75" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019ffbb6-9f66-757e-a5b0-71681180fa75" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019ffbb6-9f66-775a-8e83-2d2ffdfd9abe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019ffbb6-9f66-775a-8e83-2d2ffdfd9abe" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-9f66-79d2-aead-41921c5a7f5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-9f66-79d2-aead-41921c5a7f5c" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsForeignCurrencyForwardContractsParenthetical_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestmentsForeignCurrencyForwardContractsParenthetical_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsForeignCurrencyForwardContractsParenthetical_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7f39-906a-1f7ceeca9dc6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-74e7-8b7b-55231033065c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7f39-906a-1f7ceeca9dc6" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-74e7-8b7b-55231033065c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyDerivativesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7f39-906a-1f7ceeca9dc6" xlink:to="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ffbb6-9f66-7188-9088-1e13623d87d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ffbb6-9f66-7188-9088-1e13623d87d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount_019ffbb6-9f66-7f34-832c-d7096bee4840" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeAssetNotionalAmount_019ffbb6-9f66-7f34-832c-d7096bee4840" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019ffbb6-9f66-757e-a5b0-71681180fa75" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019ffbb6-9f66-757e-a5b0-71681180fa75" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019ffbb6-9f66-775a-8e83-2d2ffdfd9abe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019ffbb6-9f66-775a-8e83-2d2ffdfd9abe" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-9f66-79d2-aead-41921c5a7f5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ForeignCurrencyDerivativesAbstract_019ffbb6-9f66-72df-a7ae-9f17379d434f" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-9f66-79d2-aead-41921c5a7f5c" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsAdditionalInformationParenthetical" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestmentsAdditionalInformationParenthetical"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsAdditionalInformationParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7064-87ea-51cb7ccc30bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7823-8e7e-9aa3d7b103ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7064-87ea-51cb7ccc30bc" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7823-8e7e-9aa3d7b103ba" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019ffbb6-9f66-7a4c-beab-b6c059d6b2ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7823-8e7e-9aa3d7b103ba" xlink:to="loc_us-gaap_DebtInstrumentAxis_019ffbb6-9f66-7a4c-beab-b6c059d6b2ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-9f66-7a4c-beab-b6c059d6b2ff_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-9f66-7a4c-beab-b6c059d6b2ff" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-9f66-7a4c-beab-b6c059d6b2ff_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-9f66-70cd-8012-2b21844f1d5e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-9f66-7a4c-beab-b6c059d6b2ff" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-9f66-70cd-8012-2b21844f1d5e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February2019CreditFacilityMember_019ffbb6-9f66-775b-acd2-e1bc9f0f595d" xlink:href="bbdc-20260930.xsd#bbdc_February2019CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-9f66-70cd-8012-2b21844f1d5e" xlink:to="loc_bbdc_February2019CreditFacilityMember_019ffbb6-9f66-775b-acd2-e1bc9f0f595d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-9f66-7826-87e3-d3cbcf7719d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-9f66-7823-8e7e-9aa3d7b103ba" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-9f66-7826-87e3-d3cbcf7719d6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-9f66-7826-87e3-d3cbcf7719d6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-9f66-7826-87e3-d3cbcf7719d6" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-9f66-7826-87e3-d3cbcf7719d6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-9f66-7783-9e62-9cb16f69da55" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-9f66-7826-87e3-d3cbcf7719d6" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-9f66-7783-9e62-9cb16f69da55" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019ffbb6-9f66-75fd-8bd8-524117da8668" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-9f66-7783-9e62-9cb16f69da55" xlink:to="loc_us-gaap_LineOfCreditMember_019ffbb6-9f66-75fd-8bd8-524117da8668" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019ffbb6-9f66-7f73-8140-c653a29f3b1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedPercentOfNetAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7064-87ea-51cb7ccc30bc" xlink:to="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019ffbb6-9f66-7f73-8140-c653a29f3b1f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedNonQualifyingAssets_019ffbb6-9f66-7131-80ee-3c49825df2f4" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedNonQualifyingAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7064-87ea-51cb7ccc30bc" xlink:to="loc_bbdc_InvestmentOwnedNonQualifyingAssets_019ffbb6-9f66-7131-80ee-3c49825df2f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019ffbb6-9f66-7b38-b9ba-5e4e2b3fbc87" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-9f66-7064-87ea-51cb7ccc30bc" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019ffbb6-9f66-7b38-b9ba-5e4e2b3fbc87" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsScheduleOfInvestmentsParenthetical" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestmentsScheduleOfInvestmentsParenthetical"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsScheduleOfInvestmentsParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7071-8935-225b9d1bbbbc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7071-8935-225b9d1bbbbc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f66-746d-bba2-b5c0ae2d83c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7071-8935-225b9d1bbbbc" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f66-746d-bba2-b5c0ae2d83c5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f66-7e7a-9571-2a783761f0de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7071-8935-225b9d1bbbbc" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f66-7e7a-9571-2a783761f0de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-9f66-77f9-b7e4-ed9a0cd1a5b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-9f66-77f9-b7e4-ed9a0cd1a5b8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerNameAxis_019ffbb6-9f66-7b74-b2c5-4a74875be133" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:to="loc_us-gaap_InvestmentIssuerNameAxis_019ffbb6-9f66-7b74-b2c5-4a74875be133" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7b74-b2c5-4a74875be133_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerNameAxis_019ffbb6-9f66-7b74-b2c5-4a74875be133" xlink:to="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7b74-b2c5-4a74875be133_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerNameAxis_019ffbb6-9f66-7b74-b2c5-4a74875be133" xlink:to="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BiolamGroupMember_019ffbb6-9f66-7cd4-9a89-ff7497d702d0" xlink:href="bbdc-20260930.xsd#bbdc_BiolamGroupMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_BiolamGroupMember_019ffbb6-9f66-7cd4-9a89-ff7497d702d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CelebrationBidcoLLCMember_019ffbb6-9f66-77f2-bb43-fad5ca570dea" xlink:href="bbdc-20260930.xsd#bbdc_CelebrationBidcoLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_CelebrationBidcoLLCMember_019ffbb6-9f66-77f2-bb43-fad5ca570dea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CoastalMarinaHoldingsLLCMember_019ffbb6-9f66-7e8c-85cf-e1597fec254e" xlink:href="bbdc-20260930.xsd#bbdc_CoastalMarinaHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_CoastalMarinaHoldingsLLCMember_019ffbb6-9f66-7e8c-85cf-e1597fec254e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EclipseBusinessCapitalLLCMember_019ffbb6-9f66-70e7-9034-c3522d48e438" xlink:href="bbdc-20260930.xsd#bbdc_EclipseBusinessCapitalLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_EclipseBusinessCapitalLLCMember_019ffbb6-9f66-70e7-9034-c3522d48e438" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EMIPortaHoldcoLLCMember_019ffbb6-9f66-7229-8b84-83bcd25864b2" xlink:href="bbdc-20260930.xsd#bbdc_EMIPortaHoldcoLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_EMIPortaHoldcoLLCMember_019ffbb6-9f66-7229-8b84-83bcd25864b2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-7bf0-a468-8362ad9ff931" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-7bf0-a468-8362ad9ff931" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PolicyServicesCompanyLLCMember_019ffbb6-9f66-7ca5-b075-288b32dc4ac8" xlink:href="bbdc-20260930.xsd#bbdc_PolicyServicesCompanyLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_PolicyServicesCompanyLLCMember_019ffbb6-9f66-7ca5-b075-288b32dc4ac8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RocadeHoldingsLLCMember_019ffbb6-9f66-74de-8e1f-f4cfe8423abe" xlink:href="bbdc-20260930.xsd#bbdc_RocadeHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_RocadeHoldingsLLCMember_019ffbb6-9f66-74de-8e1f-f4cfe8423abe" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-764f-856c-4c885ef16574" xlink:href="bbdc-20260930.xsd#bbdc_SierraSeniorLoanStrategyJVILLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-764f-856c-4c885ef16574" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SkyvaultHoldingsLLCMember_019ffbb6-9f66-7ad2-a617-63f8050dd15f" xlink:href="bbdc-20260930.xsd#bbdc_SkyvaultHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_SkyvaultHoldingsLLCMember_019ffbb6-9f66-7ad2-a617-63f8050dd15f" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7a90-b5ac-8967a38c0e3e" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7a90-b5ac-8967a38c0e3e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-7c12-84b6-e567e7f8c4bd" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-7c12-84b6-e567e7f8c4bd" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ZeppelinBidcoLimitedMember_019ffbb6-9f66-77b2-b16e-c8d57ce9c1e1" xlink:href="bbdc-20260930.xsd#bbdc_ZeppelinBidcoLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_ZeppelinBidcoLimitedMember_019ffbb6-9f66-77b2-b16e-c8d57ce9c1e1" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BlackAngusSteakhousesLLCMember_019ffbb6-9f66-7395-946b-235bcbdbd683" xlink:href="bbdc-20260930.xsd#bbdc_BlackAngusSteakhousesLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_BlackAngusSteakhousesLLCMember_019ffbb6-9f66-7395-946b-235bcbdbd683" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MVCAutomotiveGroupGmbHMember_019ffbb6-9f66-70bf-b4c5-e0c2e507715c" xlink:href="bbdc-20260930.xsd#bbdc_MVCAutomotiveGroupGmbHMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_MVCAutomotiveGroupGmbHMember_019ffbb6-9f66-70bf-b4c5-e0c2e507715c" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MVCPrivateEquityFundLPMember_019ffbb6-9f66-71b0-b790-41fde9f92008" xlink:href="bbdc-20260930.xsd#bbdc_MVCPrivateEquityFundLPMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_MVCPrivateEquityFundLPMember_019ffbb6-9f66-71b0-b790-41fde9f92008" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SecurityHoldingsBVMember_019ffbb6-9f66-7bcd-a76a-a588b2946fa3" xlink:href="bbdc-20260930.xsd#bbdc_SecurityHoldingsBVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_SecurityHoldingsBVMember_019ffbb6-9f66-7bcd-a76a-a588b2946fa3" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7930-bd92-696a8215167c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7930-bd92-696a8215167c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7930-bd92-696a8215167c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7930-bd92-696a8215167c" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7930-bd92-696a8215167c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7930-bd92-696a8215167c" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-716e-9138-35e9db101fe0" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-716e-9138-35e9db101fe0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-799e-ad2b-ecbe09254c58" xlink:href="bbdc-20260930.xsd#bbdc_SierraSeniorLoanStrategyJVILLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:to="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-799e-ad2b-ecbe09254c58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7566-ae16-a870bf804304" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7566-ae16-a870bf804304" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-7426-8b29-a0681e7acf61" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-7426-8b29-a0681e7acf61" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a013-76b8-a207-2297a90759e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a013-76b8-a207-2297a90759e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions_019ffbb6-a013-74c0-955c-6a497eb75177" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions_019ffbb6-a013-74c0-955c-6a497eb75177" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions_019ffbb6-a013-7588-9cda-6e868171fd0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions_019ffbb6-a013-7588-9cda-6e868171fd0d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeRealizedGainLossOperatingBeforeTax_019ffbb6-a013-778f-9284-3f7b360e831c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeRealizedGainLossOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeRealizedGainLossOperatingBeforeTax_019ffbb6-a013-778f-9284-3f7b360e831c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeUnrealizedGainLossOperatingBeforeTax_019ffbb6-a013-7b7c-8b0a-2356842bee28" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeUnrealizedGainLossOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeUnrealizedGainLossOperatingBeforeTax_019ffbb6-a013-7b7c-8b0a-2356842bee28" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a013-78eb-8a03-2bb5cee7fe04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeSecurities_019ffbb6-a013-7b83-bc96-6a6306711d1e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestAndDividendIncomeSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InterestAndDividendIncomeSecurities_019ffbb6-a013-7b83-bc96-6a6306711d1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InterestAndDividendIncomeSecuritiesOperatingIncludingTrueUpAdjustment_019ffbb6-a013-7234-831d-7398df4c5ed7" xlink:href="bbdc-20260930.xsd#bbdc_InterestAndDividendIncomeSecuritiesOperatingIncludingTrueUpAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_bbdc_InterestAndDividendIncomeSecuritiesOperatingIncludingTrueUpAdjustment_019ffbb6-a013-7234-831d-7398df4c5ed7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentBasisSpreadVariableRate_019ffbb6-a013-704d-9736-4a8e70d39a90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentBasisSpreadVariableRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentBasisSpreadVariableRate_019ffbb6-a013-704d-9736-4a8e70d39a90" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRatePaidInKind_019ffbb6-a013-77fa-9ce0-2d79fcbf27d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRatePaidInKind"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentInterestRatePaidInKind_019ffbb6-a013-77fa-9ce0-2d79fcbf27d5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedBalanceShares_019ffbb6-a013-7112-aac6-434eee9a5411" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedBalanceShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentOwnedBalanceShares_019ffbb6-a013-7112-aac6-434eee9a5411" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRate_019ffbb6-a013-764c-927c-097fe7cf03e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentInterestRate_019ffbb6-a013-764c-927c-097fe7cf03e2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019ffbb6-a013-7964-ad80-621482058049" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019ffbb6-a013-7964-ad80-621482058049" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsScheduleOfInvestmentsParenthetical_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#UnauditedConsolidatedScheduleofInvestmentsScheduleOfInvestmentsParenthetical_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/UnauditedConsolidatedScheduleofInvestmentsScheduleOfInvestmentsParenthetical_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7071-8935-225b9d1bbbbc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerAffiliationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationAxis_019ffbb6-9f66-76d6-bcb8-1ffd60992eeb" xlink:to="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7071-8935-225b9d1bbbbc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f66-746d-bba2-b5c0ae2d83c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7071-8935-225b9d1bbbbc" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerNoncontrolledMember_019ffbb6-9f66-746d-bba2-b5c0ae2d83c5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f66-7e7a-9571-2a783761f0de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentAffiliatedIssuerControlledMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerAffiliationDomain_019ffbb6-9f66-7071-8935-225b9d1bbbbc" xlink:to="loc_us-gaap_InvestmentAffiliatedIssuerControlledMember_019ffbb6-9f66-7e7a-9571-2a783761f0de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerNameAxis_019ffbb6-9f66-7b74-b2c5-4a74875be133" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:to="loc_us-gaap_InvestmentIssuerNameAxis_019ffbb6-9f66-7b74-b2c5-4a74875be133" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7b74-b2c5-4a74875be133_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentIssuerNameAxis_019ffbb6-9f66-7b74-b2c5-4a74875be133" xlink:to="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7b74-b2c5-4a74875be133_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIssuerNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentIssuerNameAxis_019ffbb6-9f66-7b74-b2c5-4a74875be133" xlink:to="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BiolamGroupMember_019ffbb6-9f66-7cd4-9a89-ff7497d702d0" xlink:href="bbdc-20260930.xsd#bbdc_BiolamGroupMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_BiolamGroupMember_019ffbb6-9f66-7cd4-9a89-ff7497d702d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CelebrationBidcoLLCMember_019ffbb6-9f66-77f2-bb43-fad5ca570dea" xlink:href="bbdc-20260930.xsd#bbdc_CelebrationBidcoLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_CelebrationBidcoLLCMember_019ffbb6-9f66-77f2-bb43-fad5ca570dea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CoastalMarinaHoldingsLLCMember_019ffbb6-9f66-7e8c-85cf-e1597fec254e" xlink:href="bbdc-20260930.xsd#bbdc_CoastalMarinaHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_CoastalMarinaHoldingsLLCMember_019ffbb6-9f66-7e8c-85cf-e1597fec254e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EclipseBusinessCapitalLLCMember_019ffbb6-9f66-70e7-9034-c3522d48e438" xlink:href="bbdc-20260930.xsd#bbdc_EclipseBusinessCapitalLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_EclipseBusinessCapitalLLCMember_019ffbb6-9f66-70e7-9034-c3522d48e438" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EMIPortaHoldcoLLCMember_019ffbb6-9f66-7229-8b84-83bcd25864b2" xlink:href="bbdc-20260930.xsd#bbdc_EMIPortaHoldcoLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_EMIPortaHoldcoLLCMember_019ffbb6-9f66-7229-8b84-83bcd25864b2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-7bf0-a468-8362ad9ff931" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-7bf0-a468-8362ad9ff931" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PolicyServicesCompanyLLCMember_019ffbb6-9f66-7ca5-b075-288b32dc4ac8" xlink:href="bbdc-20260930.xsd#bbdc_PolicyServicesCompanyLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_PolicyServicesCompanyLLCMember_019ffbb6-9f66-7ca5-b075-288b32dc4ac8" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RocadeHoldingsLLCMember_019ffbb6-9f66-74de-8e1f-f4cfe8423abe" xlink:href="bbdc-20260930.xsd#bbdc_RocadeHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_RocadeHoldingsLLCMember_019ffbb6-9f66-74de-8e1f-f4cfe8423abe" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-764f-856c-4c885ef16574" xlink:href="bbdc-20260930.xsd#bbdc_SierraSeniorLoanStrategyJVILLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-764f-856c-4c885ef16574" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SkyvaultHoldingsLLCMember_019ffbb6-9f66-7ad2-a617-63f8050dd15f" xlink:href="bbdc-20260930.xsd#bbdc_SkyvaultHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_SkyvaultHoldingsLLCMember_019ffbb6-9f66-7ad2-a617-63f8050dd15f" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7a90-b5ac-8967a38c0e3e" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7a90-b5ac-8967a38c0e3e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-7c12-84b6-e567e7f8c4bd" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-7c12-84b6-e567e7f8c4bd" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ZeppelinBidcoLimitedMember_019ffbb6-9f66-77b2-b16e-c8d57ce9c1e1" xlink:href="bbdc-20260930.xsd#bbdc_ZeppelinBidcoLimitedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_ZeppelinBidcoLimitedMember_019ffbb6-9f66-77b2-b16e-c8d57ce9c1e1" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BlackAngusSteakhousesLLCMember_019ffbb6-9f66-7395-946b-235bcbdbd683" xlink:href="bbdc-20260930.xsd#bbdc_BlackAngusSteakhousesLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_BlackAngusSteakhousesLLCMember_019ffbb6-9f66-7395-946b-235bcbdbd683" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MVCAutomotiveGroupGmbHMember_019ffbb6-9f66-70bf-b4c5-e0c2e507715c" xlink:href="bbdc-20260930.xsd#bbdc_MVCAutomotiveGroupGmbHMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_MVCAutomotiveGroupGmbHMember_019ffbb6-9f66-70bf-b4c5-e0c2e507715c" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MVCPrivateEquityFundLPMember_019ffbb6-9f66-71b0-b790-41fde9f92008" xlink:href="bbdc-20260930.xsd#bbdc_MVCPrivateEquityFundLPMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_MVCPrivateEquityFundLPMember_019ffbb6-9f66-71b0-b790-41fde9f92008" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SecurityHoldingsBVMember_019ffbb6-9f66-7bcd-a76a-a588b2946fa3" xlink:href="bbdc-20260930.xsd#bbdc_SecurityHoldingsBVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentIssuerNameDomain_019ffbb6-9f66-7ea4-851f-ff1f31cbe247" xlink:to="loc_bbdc_SecurityHoldingsBVMember_019ffbb6-9f66-7bcd-a76a-a588b2946fa3" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7930-bd92-696a8215167c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019ffbb6-9f66-703f-8b1b-603740a5484d" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7930-bd92-696a8215167c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7930-bd92-696a8215167c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7930-bd92-696a8215167c" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7930-bd92-696a8215167c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-9f66-7930-bd92-696a8215167c" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-716e-9138-35e9db101fe0" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-9f66-716e-9138-35e9db101fe0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-799e-ad2b-ecbe09254c58" xlink:href="bbdc-20260930.xsd#bbdc_SierraSeniorLoanStrategyJVILLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:to="loc_bbdc_SierraSeniorLoanStrategyJVILLCMember_019ffbb6-9f66-799e-ad2b-ecbe09254c58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7566-ae16-a870bf804304" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-9f66-7566-ae16-a870bf804304" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-7426-8b29-a0681e7acf61" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-9f66-7795-bc11-c3c195f02bc1" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-9f66-7426-8b29-a0681e7acf61" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a013-76b8-a207-2297a90759e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a013-76b8-a207-2297a90759e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions_019ffbb6-a013-74c0-955c-6a497eb75177" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions_019ffbb6-a013-74c0-955c-6a497eb75177" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions_019ffbb6-a013-7588-9cda-6e868171fd0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions_019ffbb6-a013-7588-9cda-6e868171fd0d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeRealizedGainLossOperatingBeforeTax_019ffbb6-a013-778f-9284-3f7b360e831c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeRealizedGainLossOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeRealizedGainLossOperatingBeforeTax_019ffbb6-a013-778f-9284-3f7b360e831c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeUnrealizedGainLossOperatingBeforeTax_019ffbb6-a013-7b7c-8b0a-2356842bee28" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeUnrealizedGainLossOperatingBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValueRollForward_019ffbb6-9f66-74f8-aced-928f106d2913" xlink:to="loc_us-gaap_DerivativeAndForeignCurrencyTransactionPriceChangeUnrealizedGainLossOperatingBeforeTax_019ffbb6-a013-7b7c-8b0a-2356842bee28" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a013-78eb-8a03-2bb5cee7fe04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeSecurities_019ffbb6-a013-7b83-bc96-6a6306711d1e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestAndDividendIncomeSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InterestAndDividendIncomeSecurities_019ffbb6-a013-7b83-bc96-6a6306711d1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InterestAndDividendIncomeSecuritiesOperatingIncludingTrueUpAdjustment_019ffbb6-a013-7234-831d-7398df4c5ed7" xlink:href="bbdc-20260930.xsd#bbdc_InterestAndDividendIncomeSecuritiesOperatingIncludingTrueUpAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_bbdc_InterestAndDividendIncomeSecuritiesOperatingIncludingTrueUpAdjustment_019ffbb6-a013-7234-831d-7398df4c5ed7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentBasisSpreadVariableRate_019ffbb6-a013-704d-9736-4a8e70d39a90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentBasisSpreadVariableRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentBasisSpreadVariableRate_019ffbb6-a013-704d-9736-4a8e70d39a90" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRatePaidInKind_019ffbb6-a013-77fa-9ce0-2d79fcbf27d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRatePaidInKind"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentInterestRatePaidInKind_019ffbb6-a013-77fa-9ce0-2d79fcbf27d5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedBalanceShares_019ffbb6-a013-7112-aac6-434eee9a5411" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedBalanceShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentOwnedBalanceShares_019ffbb6-a013-7112-aac6-434eee9a5411" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRate_019ffbb6-a013-764c-927c-097fe7cf03e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_InvestmentInterestRate_019ffbb6-a013-764c-927c-097fe7cf03e2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019ffbb6-a013-7964-ad80-621482058049" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019ffbb6-9f66-7571-a3f7-1ee356a74526" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019ffbb6-a013-7964-ad80-621482058049" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/ORGANIZATIONBUSINESSANDBASISOFPRESENTATIONDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#ORGANIZATIONBUSINESSANDBASISOFPRESENTATIONDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/ORGANIZATIONBUSINESSANDBASISOFPRESENTATIONDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramLineItems_019ffbb6-a014-7d47-801c-b0c7f3866478" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramTable_019ffbb6-a014-7d97-bcfe-026f2a7f9ce5" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_ShareRepurchaseProgramLineItems_019ffbb6-a014-7d47-801c-b0c7f3866478" xlink:to="loc_srt_ShareRepurchaseProgramTable_019ffbb6-a014-7d97-bcfe-026f2a7f9ce5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_019ffbb6-a014-7a86-9ac4-459952cc6116" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_ShareRepurchaseProgramTable_019ffbb6-a014-7d97-bcfe-026f2a7f9ce5" xlink:to="loc_srt_ShareRepurchaseProgramAxis_019ffbb6-a014-7a86-9ac4-459952cc6116" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019ffbb6-a014-7a86-9ac4-459952cc6116_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019ffbb6-a014-7a86-9ac4-459952cc6116" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019ffbb6-a014-7a86-9ac4-459952cc6116_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_019ffbb6-a014-7cff-878e-804c49ebf66b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_019ffbb6-a014-7a86-9ac4-459952cc6116" xlink:to="loc_srt_ShareRepurchaseProgramDomain_019ffbb6-a014-7cff-878e-804c49ebf66b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February202025ProgramMember_019ffbb6-a014-7fcc-bb79-491b22c2cd06" xlink:href="bbdc-20260930.xsd#bbdc_February202025ProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_019ffbb6-a014-7cff-878e-804c49ebf66b" xlink:to="loc_bbdc_February202025ProgramMember_019ffbb6-a014-7fcc-bb79-491b22c2cd06" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February192026ProgramMember_019ffbb6-a014-7d26-90bc-b2a8708a8b96" xlink:href="bbdc-20260930.xsd#bbdc_February192026ProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_019ffbb6-a014-7cff-878e-804c49ebf66b" xlink:to="loc_bbdc_February192026ProgramMember_019ffbb6-a014-7d26-90bc-b2a8708a8b96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ShareRepurchaseProgramTerm_019ffbb6-a014-770b-90bd-a8ad19140df4" xlink:href="bbdc-20260930.xsd#bbdc_ShareRepurchaseProgramTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramLineItems_019ffbb6-a014-7d47-801c-b0c7f3866478" xlink:to="loc_bbdc_ShareRepurchaseProgramTerm_019ffbb6-a014-770b-90bd-a8ad19140df4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019ffbb6-a014-7af4-8e66-a76190def96c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramLineItems_019ffbb6-a014-7d47-801c-b0c7f3866478" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019ffbb6-a014-7af4-8e66-a76190def96c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_019ffbb6-a014-7961-bc2c-8d609ee2fb32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramLineItems_019ffbb6-a014-7d47-801c-b0c7f3866478" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_019ffbb6-a014-7961-bc2c-8d609ee2fb32" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_StockRepurchasedPurchaseProgramAverageCostPerShare_019ffbb6-a014-76a8-b823-007e1f7c7447" xlink:href="bbdc-20260930.xsd#bbdc_StockRepurchasedPurchaseProgramAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramLineItems_019ffbb6-a014-7d47-801c-b0c7f3866478" xlink:to="loc_bbdc_StockRepurchasedPurchaseProgramAverageCostPerShare_019ffbb6-a014-76a8-b823-007e1f7c7447" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/AGREEMENTSANDRELATEDPARTYTRANSACTIONSDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#AGREEMENTSANDRELATEDPARTYTRANSACTIONSDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/AGREEMENTSANDRELATEDPARTYTRANSACTIONSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019ffbb6-a014-78ae-bbb4-ccbf068dfdae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019ffbb6-a014-78ae-bbb4-ccbf068dfdae" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_019ffbb6-a014-7d37-a12e-3f6e7238b2da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019ffbb6-a014-78ae-bbb4-ccbf068dfdae" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_019ffbb6-a014-7d37-a12e-3f6e7238b2da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7d37-a12e-3f6e7238b2da_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_019ffbb6-a014-7d37-a12e-3f6e7238b2da" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7d37-a12e-3f6e7238b2da_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_019ffbb6-a014-7d37-a12e-3f6e7238b2da" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_OriginalAdvisoryAgreementQuarterlyIncentiveFeeRateMember_019ffbb6-a014-7df8-84e0-31803754d339" xlink:href="bbdc-20260930.xsd#bbdc_OriginalAdvisoryAgreementQuarterlyIncentiveFeeRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_OriginalAdvisoryAgreementQuarterlyIncentiveFeeRateMember_019ffbb6-a014-7df8-84e0-31803754d339" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AmendedAndRestatedAdvisoryAgreementMember_019ffbb6-a014-7285-ac0a-ea0388b3f5ba" xlink:href="bbdc-20260930.xsd#bbdc_AmendedAndRestatedAdvisoryAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_AmendedAndRestatedAdvisoryAgreementMember_019ffbb6-a014-7285-ac0a-ea0388b3f5ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewBaringsBDCAdvisoryAgreementQuarterlyIncentiveFeeRateMember_019ffbb6-a014-70f5-8e9d-4f2abb58b8f8" xlink:href="bbdc-20260930.xsd#bbdc_NewBaringsBDCAdvisoryAgreementQuarterlyIncentiveFeeRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_NewBaringsBDCAdvisoryAgreementQuarterlyIncentiveFeeRateMember_019ffbb6-a014-70f5-8e9d-4f2abb58b8f8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_OriginalAdvisoryAgreementAnnualizedIncentiveFeeRateMember_019ffbb6-a014-7096-99b9-76fd17c1ca0f" xlink:href="bbdc-20260930.xsd#bbdc_OriginalAdvisoryAgreementAnnualizedIncentiveFeeRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_OriginalAdvisoryAgreementAnnualizedIncentiveFeeRateMember_019ffbb6-a014-7096-99b9-76fd17c1ca0f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewBaringsBDCAdvisoryAgreementAnnualizedIncentiveFeeRateMember_019ffbb6-a014-705a-9258-4fd31878cbdb" xlink:href="bbdc-20260930.xsd#bbdc_NewBaringsBDCAdvisoryAgreementAnnualizedIncentiveFeeRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_NewBaringsBDCAdvisoryAgreementAnnualizedIncentiveFeeRateMember_019ffbb6-a014-705a-9258-4fd31878cbdb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentAdvisoryAgreementMember_019ffbb6-a014-7114-8b4a-9982bff48570" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentAdvisoryAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentAdvisoryAgreementMember_019ffbb6-a014-7114-8b4a-9982bff48570" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementMember_019ffbb6-a014-72f4-82ff-4688a349def6" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementMember_019ffbb6-a014-72f4-82ff-4688a349def6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRateQuarterlyHurdleRateMember_019ffbb6-a014-7a34-aee4-125ba34c7e60" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRateQuarterlyHurdleRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRateQuarterlyHurdleRateMember_019ffbb6-a014-7a34-aee4-125ba34c7e60" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRateAnnualizedHurdleRateMember_019ffbb6-a014-73c8-8381-d24c14ba221b" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRateAnnualizedHurdleRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRateAnnualizedHurdleRateMember_019ffbb6-a014-73c8-8381-d24c14ba221b" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeBelowCatchUpThresholdMember_019ffbb6-a014-7747-aa0f-fb666460e3a9" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeBelowCatchUpThresholdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeBelowCatchUpThresholdMember_019ffbb6-a014-7747-aa0f-fb666460e3a9" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRateQuarterlyCatchUpThresholdMember_019ffbb6-a014-7561-89ee-ece38ff722c4" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRateQuarterlyCatchUpThresholdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRateQuarterlyCatchUpThresholdMember_019ffbb6-a014-7561-89ee-ece38ff722c4" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRateAnnualCatchUpThresholdMember_019ffbb6-a014-7985-8074-e56f3633fab5" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRateAnnualCatchUpThresholdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRateAnnualCatchUpThresholdMember_019ffbb6-a014-7985-8074-e56f3633fab5" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeExceedsCatchUpThresholdMember_019ffbb6-a014-7b31-adf7-83be4d1ad1dd" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeExceedsCatchUpThresholdMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeExceedsCatchUpThresholdMember_019ffbb6-a014-7b31-adf7-83be4d1ad1dd" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeForTrailingTwelveQuartersExceedsCatchUpAmountMember_019ffbb6-a014-7f56-b682-01528dca5d93" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeForTrailingTwelveQuartersExceedsCatchUpAmountMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeForTrailingTwelveQuartersExceedsCatchUpAmountMember_019ffbb6-a014-7f56-b682-01528dca5d93" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRateCumulativePreIncentiveFeeNetReturnMember_019ffbb6-a014-7c4a-9349-2568035a17c4" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRateCumulativePreIncentiveFeeNetReturnMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRateCumulativePreIncentiveFeeNetReturnMember_019ffbb6-a014-7c4a-9349-2568035a17c4" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRateRealizedCapitalGainsMember_019ffbb6-a014-7809-8154-6620a7e07876" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRateRealizedCapitalGainsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRateRealizedCapitalGainsMember_019ffbb6-a014-7809-8154-6620a7e07876" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeMember_019ffbb6-a014-7bb7-914d-97f791d0f753" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRatePreIncentiveFeeNetInvestmentIncomeMember_019ffbb6-a014-7bb7-914d-97f791d0f753" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentManagementAgreementIncentiveRateCapitalGainFeeMember_019ffbb6-a014-78cf-8438-90da38d86d69" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentManagementAgreementIncentiveRateCapitalGainFeeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_InvestmentManagementAgreementIncentiveRateCapitalGainFeeMember_019ffbb6-a014-78cf-8438-90da38d86d69" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MVCCreditSupportAgreementMember_019ffbb6-a014-7a13-a146-92f78640f046" xlink:href="bbdc-20260930.xsd#bbdc_MVCCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_MVCCreditSupportAgreementMember_019ffbb6-a014-7a13-a146-92f78640f046" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MVCCreditSupportAgreementCoveredCreditLossesMinimumMember_019ffbb6-a014-7cdd-8415-ff01eb1a7b0e" xlink:href="bbdc-20260930.xsd#bbdc_MVCCreditSupportAgreementCoveredCreditLossesMinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_MVCCreditSupportAgreementCoveredCreditLossesMinimumMember_019ffbb6-a014-7cdd-8415-ff01eb1a7b0e" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a014-75cd-beac-2a12c35f0e6a" xlink:href="bbdc-20260930.xsd#bbdc_PriorSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a014-75cd-beac-2a12c35f0e6a" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PriorSierraCreditSupportAgreementCoveredCreditLossesMinimumMember_019ffbb6-a014-7418-8898-003446416862" xlink:href="bbdc-20260930.xsd#bbdc_PriorSierraCreditSupportAgreementCoveredCreditLossesMinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_PriorSierraCreditSupportAgreementCoveredCreditLossesMinimumMember_019ffbb6-a014-7418-8898-003446416862" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-a014-79c0-a945-a0d37e39c638" xlink:href="bbdc-20260930.xsd#bbdc_NewSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-a014-79c0-a945-a0d37e39c638" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewSierraCreditSupportAgreementCoveredCreditLossesMinimumMember_019ffbb6-a014-74a2-8a48-5d5308e01954" xlink:href="bbdc-20260930.xsd#bbdc_NewSierraCreditSupportAgreementCoveredCreditLossesMinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019ffbb6-a014-7acb-929d-24228d0c981e" xlink:to="loc_bbdc_NewSierraCreditSupportAgreementCoveredCreditLossesMinimumMember_019ffbb6-a014-74a2-8a48-5d5308e01954" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a014-7816-b4c1-a2fbb406aa11" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019ffbb6-a014-78ae-bbb4-ccbf068dfdae" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a014-7816-b4c1-a2fbb406aa11" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019ffbb6-a014-7816-b4c1-a2fbb406aa11_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a014-7816-b4c1-a2fbb406aa11" xlink:to="loc_us-gaap_RelatedPartyDomain_019ffbb6-a014-7816-b4c1-a2fbb406aa11_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019ffbb6-a014-7377-b833-9d370000c944" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a014-7816-b4c1-a2fbb406aa11" xlink:to="loc_us-gaap_RelatedPartyDomain_019ffbb6-a014-7377-b833-9d370000c944" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AffiliatedEntityMember_019ffbb6-a014-7144-a46b-926abb6c5f92" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AffiliatedEntityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019ffbb6-a014-7377-b833-9d370000c944" xlink:to="loc_srt_AffiliatedEntityMember_019ffbb6-a014-7144-a46b-926abb6c5f92" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019ffbb6-a014-705a-a88a-5ee5ce84e7bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019ffbb6-a014-7377-b833-9d370000c944" xlink:to="loc_us-gaap_RelatedPartyMember_019ffbb6-a014-705a-a88a-5ee5ce84e7bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a014-73c3-aaaf-601b605ad83f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019ffbb6-a014-78ae-bbb4-ccbf068dfdae" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a014-73c3-aaaf-601b605ad83f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-73c3-aaaf-601b605ad83f_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a014-73c3-aaaf-601b605ad83f" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-73c3-aaaf-601b605ad83f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-7476-bd6b-f24342fb156d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a014-73c3-aaaf-601b605ad83f" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-7476-bd6b-f24342fb156d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BaringsLLCMember_019ffbb6-a014-7ad2-aab2-346d934994e3" xlink:href="bbdc-20260930.xsd#bbdc_BaringsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-7476-bd6b-f24342fb156d" xlink:to="loc_bbdc_BaringsLLCMember_019ffbb6-a014-7ad2-aab2-346d934994e3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a014-7ac2-a00c-a835b6c5c0fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019ffbb6-a014-78ae-bbb4-ccbf068dfdae" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a014-7ac2-a00c-a835b6c5c0fa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a014-7ac2-a00c-a835b6c5c0fa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a014-7ac2-a00c-a835b6c5c0fa" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a014-7ac2-a00c-a835b6c5c0fa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a014-7304-a81b-510a8372489f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a014-7ac2-a00c-a835b6c5c0fa" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a014-7304-a81b-510a8372489f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MVCCreditSupportAgreementMember_019ffbb6-a014-70f7-a8af-98b09da109f1" xlink:href="bbdc-20260930.xsd#bbdc_MVCCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a014-7304-a81b-510a8372489f" xlink:to="loc_bbdc_MVCCreditSupportAgreementMember_019ffbb6-a014-70f7-a8af-98b09da109f1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a014-701d-b706-a070be13836d" xlink:href="bbdc-20260930.xsd#bbdc_PriorSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a014-7304-a81b-510a8372489f" xlink:to="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a014-701d-b706-a070be13836d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementAndServiceFeesBaseRate_019ffbb6-a014-789a-83e9-ce43563ed96c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementAndServiceFeesBaseRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_ManagementAndServiceFeesBaseRate_019ffbb6-a014-789a-83e9-ce43563ed96c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ManagementAndServiceFeesLookBackPeriodProvision_019ffbb6-a014-7486-85df-1492f6491449" xlink:href="bbdc-20260930.xsd#bbdc_ManagementAndServiceFeesLookBackPeriodProvision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_ManagementAndServiceFeesLookBackPeriodProvision_019ffbb6-a014-7486-85df-1492f6491449" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementAndServiceFeesIncentiveRate_019ffbb6-a014-77ea-8c02-83fac7738584" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementAndServiceFeesIncentiveRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_ManagementAndServiceFeesIncentiveRate_019ffbb6-a014-77ea-8c02-83fac7738584" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementAndServiceFeesRate_019ffbb6-a014-75b1-822c-21edf16e76ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementAndServiceFeesRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_ManagementAndServiceFeesRate_019ffbb6-a014-75b1-822c-21edf16e76ba" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeeExpense_019ffbb6-a014-78f4-b6e9-d135dae22d3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementFeeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_ManagementFeeExpense_019ffbb6-a014-78f4-b6e9-d135dae22d3b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeePayable_019ffbb6-a014-74ef-8ba0-d3dea0753ae2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementFeePayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_ManagementFeePayable_019ffbb6-a014-74ef-8ba0-d3dea0753ae2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RelatedPartyTransactionNumberOfComponents_019ffbb6-a014-7703-881f-721c055538fd" xlink:href="bbdc-20260930.xsd#bbdc_RelatedPartyTransactionNumberOfComponents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_RelatedPartyTransactionNumberOfComponents_019ffbb6-a014-7703-881f-721c055538fd" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncentiveFeeExpense_019ffbb6-a014-70ed-a056-4e9036e5edde" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncentiveFeeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_IncentiveFeeExpense_019ffbb6-a014-70ed-a056-4e9036e5edde" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncentiveFeePayable_019ffbb6-a014-705f-a5b9-a91e6dd45fed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncentiveFeePayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_IncentiveFeePayable_019ffbb6-a014-705f-a5b9-a91e6dd45fed" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdministrativeFeesExpense_019ffbb6-a014-7091-a9d6-ba1d60629b78" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdministrativeFeesExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_AdministrativeFeesExpense_019ffbb6-a014-7091-a9d6-ba1d60629b78" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AdministrativeFeesPayable_019ffbb6-a014-7f65-bfae-f87886518189" xlink:href="bbdc-20260930.xsd#bbdc_AdministrativeFeesPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_AdministrativeFeesPayable_019ffbb6-a014-7f65-bfae-f87886518189" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_019ffbb6-a014-7d7d-a0ed-8f2e9b46f244" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionAmountsOfTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_019ffbb6-a014-7d7d-a0ed-8f2e9b46f244" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RelatedPartyTransactionTerm_019ffbb6-a014-7caf-a501-41260c3ad17f" xlink:href="bbdc-20260930.xsd#bbdc_RelatedPartyTransactionTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_RelatedPartyTransactionTerm_019ffbb6-a014-7caf-a501-41260c3ad17f" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DerivativeExpectedProceeds_019ffbb6-a014-72fb-afe2-f955d81dc5e8" xlink:href="bbdc-20260930.xsd#bbdc_DerivativeExpectedProceeds"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_DerivativeExpectedProceeds_019ffbb6-a014-72fb-afe2-f955d81dc5e8" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ProceedsFromTerminationOfCostSharingAgreement_019ffbb6-a014-7f6f-8e15-a3d3af47dca8" xlink:href="bbdc-20260930.xsd#bbdc_ProceedsFromTerminationOfCostSharingAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_ProceedsFromTerminationOfCostSharingAgreement_019ffbb6-a014-7f6f-8e15-a3d3af47dca8" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TerminationAndCancellationAgreementPayment_019ffbb6-a014-7b9e-af21-95533445f37a" xlink:href="bbdc-20260930.xsd#bbdc_TerminationAndCancellationAgreementPayment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_TerminationAndCancellationAgreementPayment_019ffbb6-a014-7b9e-af21-95533445f37a" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsCurrent_019ffbb6-a014-7da2-8672-34370772f7d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_us-gaap_DerivativeAssetsCurrent_019ffbb6-a014-7da2-8672-34370772f7d4" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RealizedGainLossOnCreditSupportAgreement_019ffbb6-a014-7544-8c55-b5009b7c91d2" xlink:href="bbdc-20260930.xsd#bbdc_RealizedGainLossOnCreditSupportAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_RealizedGainLossOnCreditSupportAgreement_019ffbb6-a014-7544-8c55-b5009b7c91d2" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NumberOfPortfolioCompaniesCoveredUnderCreditSupportAgreement_019ffbb6-a014-7cee-88e4-fbd085584b8c" xlink:href="bbdc-20260930.xsd#bbdc_NumberOfPortfolioCompaniesCoveredUnderCreditSupportAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019ffbb6-a014-7bb1-9b66-a16cbe08cb99" xlink:to="loc_bbdc_NumberOfPortfolioCompaniesCoveredUnderCreditSupportAgreement_019ffbb6-a014-7cee-88e4-fbd085584b8c" xlink:type="arc" order="18"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofCompositionofInvestmentPortfolioatCostAndFairValueDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofCompositionofInvestmentPortfolioatCostAndFairValueDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofCompositionofInvestmentPortfolioatCostAndFairValueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-741a-b152-9b6ef96a13dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7e5c-8e09-09737c8b1cd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-741a-b152-9b6ef96a13dd" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7e5c-8e09-09737c8b1cd3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a014-760c-b0bc-d33478027f65" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7e5c-8e09-09737c8b1cd3" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a014-760c-b0bc-d33478027f65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-760c-b0bc-d33478027f65_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a014-760c-b0bc-d33478027f65" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-760c-b0bc-d33478027f65_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a014-760c-b0bc-d33478027f65" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a014-751f-87b8-35230250908b" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a014-751f-87b8-35230250908b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a014-73c3-8473-c7bf662ef054" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a014-73c3-8473-c7bf662ef054" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_StructuredProductsMember_019ffbb6-a014-7433-8682-1c078faa1bda" xlink:href="bbdc-20260930.xsd#bbdc_StructuredProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_bbdc_StructuredProductsMember_019ffbb6-a014-7433-8682-1c078faa1bda" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a014-7a57-896f-28fdd6f395d2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a014-7a57-896f-28fdd6f395d2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EquityWarrantsMember_019ffbb6-a014-7303-a76f-7ff3d78b728c" xlink:href="bbdc-20260930.xsd#bbdc_EquityWarrantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_bbdc_EquityWarrantsMember_019ffbb6-a014-7303-a76f-7ff3d78b728c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RoyaltyRightsMember_019ffbb6-a014-7f37-9da2-a318c8e18b9b" xlink:href="bbdc-20260930.xsd#bbdc_RoyaltyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_bbdc_RoyaltyRightsMember_019ffbb6-a014-7f37-9da2-a318c8e18b9b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentInJointVenturesMember_019ffbb6-a014-70b4-9a11-fa452f69cbfb" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentInJointVenturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_bbdc_InvestmentInJointVenturesMember_019ffbb6-a014-70b4-9a11-fa452f69cbfb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermInvestmentsMember_019ffbb6-a014-7f1b-96ba-4e71da1f43c0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShortTermInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_us-gaap_ShortTermInvestmentsMember_019ffbb6-a014-7f1b-96ba-4e71da1f43c0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FederalHousingAdministrationFHALoansMember_019ffbb6-a014-7dd4-a524-2ff45eebe7ac" xlink:href="bbdc-20260930.xsd#bbdc_FederalHousingAdministrationFHALoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_bbdc_FederalHousingAdministrationFHALoansMember_019ffbb6-a014-7dd4-a524-2ff45eebe7ac" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_VeteransAffairsVALoansMember_019ffbb6-a014-7c17-8822-b0a754513be1" xlink:href="bbdc-20260930.xsd#bbdc_VeteransAffairsVALoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7e03-90c1-47b354cc4a70" xlink:to="loc_bbdc_VeteransAffairsVALoansMember_019ffbb6-a014-7c17-8822-b0a754513be1" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a014-7cbc-a5d8-12a2198005cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7e5c-8e09-09737c8b1cd3" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a014-7cbc-a5d8-12a2198005cc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a014-7cbc-a5d8-12a2198005cc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a014-7cbc-a5d8-12a2198005cc" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a014-7cbc-a5d8-12a2198005cc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a014-7fb4-bbdb-93a81b9698c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a014-7cbc-a5d8-12a2198005cc" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a014-7fb4-bbdb-93a81b9698c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedAtCostMember_019ffbb6-a014-7122-a117-70c3dc7c37bc" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedAtCostMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a014-7fb4-bbdb-93a81b9698c2" xlink:to="loc_bbdc_InvestmentOwnedAtCostMember_019ffbb6-a014-7122-a117-70c3dc7c37bc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedAtFairValueMember_019ffbb6-a014-7a82-9d80-433b979dc007" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedAtFairValueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a014-7fb4-bbdb-93a81b9698c2" xlink:to="loc_bbdc_InvestmentOwnedAtFairValueMember_019ffbb6-a014-7a82-9d80-433b979dc007" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a014-72ff-af3c-c90a2d18fc5d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7e5c-8e09-09737c8b1cd3" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a014-72ff-af3c-c90a2d18fc5d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a014-72ff-af3c-c90a2d18fc5d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a014-72ff-af3c-c90a2d18fc5d" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a014-72ff-af3c-c90a2d18fc5d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a014-78e5-be1d-8086608533ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a014-72ff-af3c-c90a2d18fc5d" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a014-78e5-be1d-8086608533ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentTypeConcentrationRiskMember_019ffbb6-a014-7caf-a52e-51b2a4772ad5" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentTypeConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a014-78e5-be1d-8086608533ff" xlink:to="loc_bbdc_InvestmentTypeConcentrationRiskMember_019ffbb6-a014-7caf-a52e-51b2a4772ad5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a014-7b6b-a038-ce90daaeab22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7e5c-8e09-09737c8b1cd3" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a014-7b6b-a038-ce90daaeab22" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-7b6b-a038-ce90daaeab22_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a014-7b6b-a038-ce90daaeab22" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-7b6b-a038-ce90daaeab22_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-788d-8330-3de67fb5af79" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a014-7b6b-a038-ce90daaeab22" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-788d-8330-3de67fb5af79" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a014-72fa-b584-5073ef639cfb" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-788d-8330-3de67fb5af79" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a014-72fa-b584-5073ef639cfb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a014-7828-91a4-16070ffc7abd" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-788d-8330-3de67fb5af79" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a014-7828-91a4-16070ffc7abd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraJVMember_019ffbb6-a014-730c-a02e-2d6bcdec335d" xlink:href="bbdc-20260930.xsd#bbdc_SierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-788d-8330-3de67fb5af79" xlink:to="loc_bbdc_SierraJVMember_019ffbb6-a014-730c-a02e-2d6bcdec335d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-a014-71dd-8d97-7d95960d1fb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-741a-b152-9b6ef96a13dd" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-a014-71dd-8d97-7d95960d1fb5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019ffbb6-a014-7ebe-a4c9-6f967d0139e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-741a-b152-9b6ef96a13dd" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019ffbb6-a014-7ebe-a4c9-6f967d0139e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a014-77e9-9f02-412278d6f760" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-741a-b152-9b6ef96a13dd" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a014-77e9-9f02-412278d6f760" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019ffbb6-a014-7891-bbbb-76188ee994c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedPercentOfNetAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-741a-b152-9b6ef96a13dd" xlink:to="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019ffbb6-a014-7891-bbbb-76188ee994c3" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofInvestmentHoldingsDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofInvestmentHoldingsDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofInvestmentHoldingsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_01a0f712-0f12-7214-88ae-55164c97ec8e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_01a0f712-0f11-7f7b-99a5-c27700bf8d26" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_01a0f712-0f12-7214-88ae-55164c97ec8e" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_01a0f712-0f11-7f7b-99a5-c27700bf8d26" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_01a0f712-0f11-7858-a89e-727ed1892737" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_01a0f712-0f11-7f7b-99a5-c27700bf8d26" xlink:to="loc_us-gaap_InvestmentTypeAxis_01a0f712-0f11-7858-a89e-727ed1892737" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_01a0f712-0f11-7858-a89e-727ed1892737_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_01a0f712-0f11-7858-a89e-727ed1892737" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_01a0f712-0f11-7858-a89e-727ed1892737_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_01a0f712-0f11-7c47-bb5c-5a687581b95c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_01a0f712-0f11-7858-a89e-727ed1892737" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_01a0f712-0f11-7c47-bb5c-5a687581b95c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewPortfolioInvestmentsMember_01a0f712-0f11-701c-8291-07e484c49ab6" xlink:href="bbdc-20260930.xsd#bbdc_NewPortfolioInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_01a0f712-0f11-7c47-bb5c-5a687581b95c" xlink:to="loc_bbdc_NewPortfolioInvestmentsMember_01a0f712-0f11-701c-8291-07e484c49ab6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ExistingPortfolioMember_01a0f712-0f12-7fd7-acd7-507f2661fde1" xlink:href="bbdc-20260930.xsd#bbdc_ExistingPortfolioMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_01a0f712-0f11-7c47-bb5c-5a687581b95c" xlink:to="loc_bbdc_ExistingPortfolioMember_01a0f712-0f12-7fd7-acd7-507f2661fde1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_01a0f712-0f12-7c70-89f8-9cb91a73f4a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_01a0f712-0f12-7214-88ae-55164c97ec8e" xlink:to="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_01a0f712-0f12-7c70-89f8-9cb91a73f4a4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedNumberOfInvestmentsEnteredInto_01a0f712-0f12-7209-9c82-5430bc1371bd" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedNumberOfInvestmentsEnteredInto"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_01a0f712-0f12-7214-88ae-55164c97ec8e" xlink:to="loc_bbdc_InvestmentOwnedNumberOfInvestmentsEnteredInto_01a0f712-0f12-7209-9c82-5430bc1371bd" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSJocasseePartnersLLCDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSJocasseePartnersLLCDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSJocasseePartnersLLCDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a014-7611-9032-4d287943d79e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a014-7611-9032-4d287943d79e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-7611-9032-4d287943d79e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a014-7611-9032-4d287943d79e" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-7611-9032-4d287943d79e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-75b4-9554-b14e02aa0a93" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a014-7611-9032-4d287943d79e" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-75b4-9554-b14e02aa0a93" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a014-70e4-aad5-7bf159b5b044" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a014-75b4-9554-b14e02aa0a93" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a014-70e4-aad5-7bf159b5b044" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a014-70f5-b52e-448a282f5dd3" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a014-70f5-b52e-448a282f5dd3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a014-70f5-b52e-448a282f5dd3_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a014-70f5-b52e-448a282f5dd3" xlink:to="loc_dei_EntityDomain_019ffbb6-a014-70f5-b52e-448a282f5dd3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a014-7b3f-90d5-95f54e69620f" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a014-70f5-b52e-448a282f5dd3" xlink:to="loc_dei_EntityDomain_019ffbb6-a014-7b3f-90d5-95f54e69620f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SouthCarolinaRetirementSystemsGroupTrustMember_019ffbb6-a014-7c85-ba06-4926f3bb5e7d" xlink:href="bbdc-20260930.xsd#bbdc_SouthCarolinaRetirementSystemsGroupTrustMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a014-7b3f-90d5-95f54e69620f" xlink:to="loc_bbdc_SouthCarolinaRetirementSystemsGroupTrustMember_019ffbb6-a014-7c85-ba06-4926f3bb5e7d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a014-7ff9-b119-0779130593e3" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a014-7b3f-90d5-95f54e69620f" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a014-7ff9-b119-0779130593e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a014-700e-b8d0-dd46793cc1c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a014-700e-b8d0-dd46793cc1c7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-700e-b8d0-dd46793cc1c7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a014-700e-b8d0-dd46793cc1c7" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-700e-b8d0-dd46793cc1c7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7a58-aa86-baf2830267b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a014-700e-b8d0-dd46793cc1c7" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7a58-aa86-baf2830267b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_LongTermInvestmentsMember_019ffbb6-a014-78a0-928d-3541c6dd94f0" xlink:href="bbdc-20260930.xsd#bbdc_LongTermInvestmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a014-7a58-aa86-baf2830267b5" xlink:to="loc_bbdc_LongTermInvestmentsMember_019ffbb6-a014-78a0-928d-3541c6dd94f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019ffbb6-a014-7677-b1ad-367e82a1a455" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:to="loc_us-gaap_CreditFacilityAxis_019ffbb6-a014-7677-b1ad-367e82a1a455" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019ffbb6-a014-7677-b1ad-367e82a1a455_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019ffbb6-a014-7677-b1ad-367e82a1a455" xlink:to="loc_us-gaap_CreditFacilityDomain_019ffbb6-a014-7677-b1ad-367e82a1a455_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019ffbb6-a014-7212-959d-43b578c6ccda" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019ffbb6-a014-7677-b1ad-367e82a1a455" xlink:to="loc_us-gaap_CreditFacilityDomain_019ffbb6-a014-7212-959d-43b578c6ccda" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SubscriptionFacilityMember_019ffbb6-a014-785b-8c58-1962f1a4f9df" xlink:href="bbdc-20260930.xsd#bbdc_SubscriptionFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019ffbb6-a014-7212-959d-43b578c6ccda" xlink:to="loc_bbdc_SubscriptionFacilityMember_019ffbb6-a014-785b-8c58-1962f1a4f9df" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a014-7cab-a622-6cd448066a20" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:to="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a014-7cab-a622-6cd448066a20" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a014-7cab-a622-6cd448066a20_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a014-7cab-a622-6cd448066a20" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a014-7cab-a622-6cd448066a20_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a014-71c3-b9d5-4e8683f93d2c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a014-7cab-a622-6cd448066a20" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a014-71c3-b9d5-4e8683f93d2c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BankOfAmericaSubscriptionFacilityMember_019ffbb6-a014-7771-9ae4-9c8ac51b4520" xlink:href="bbdc-20260930.xsd#bbdc_BankOfAmericaSubscriptionFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a014-71c3-b9d5-4e8683f93d2c" xlink:to="loc_bbdc_BankOfAmericaSubscriptionFacilityMember_019ffbb6-a014-7771-9ae4-9c8ac51b4520" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CitibankNASubscriptionFacilityMember_019ffbb6-a014-7ac0-b4b4-2dab633ab980" xlink:href="bbdc-20260930.xsd#bbdc_CitibankNASubscriptionFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a014-71c3-b9d5-4e8683f93d2c" xlink:to="loc_bbdc_CitibankNASubscriptionFacilityMember_019ffbb6-a014-7ac0-b4b4-2dab633ab980" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TermDebtSecuritizationMember_019ffbb6-a014-75f0-aa24-ecc85db3e0d9" xlink:href="bbdc-20260930.xsd#bbdc_TermDebtSecuritizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a014-71c3-b9d5-4e8683f93d2c" xlink:to="loc_bbdc_TermDebtSecuritizationMember_019ffbb6-a014-75f0-aa24-ecc85db3e0d9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a014-710c-9e75-b6ef12d66c37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a014-710c-9e75-b6ef12d66c37" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a014-710c-9e75-b6ef12d66c37_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a014-710c-9e75-b6ef12d66c37" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a014-710c-9e75-b6ef12d66c37_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a014-7e10-9a25-4821a6742b89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a014-710c-9e75-b6ef12d66c37" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a014-7e10-9a25-4821a6742b89" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019ffbb6-a014-7cf2-9444-bd8e833b473e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a014-7e10-9a25-4821a6742b89" xlink:to="loc_us-gaap_LineOfCreditMember_019ffbb6-a014-7cf2-9444-bd8e833b473e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a014-7ece-aa2f-b39ea224556e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-77b7-a83f-639a57121bc0" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a014-7ece-aa2f-b39ea224556e" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-7ece-aa2f-b39ea224556e_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a014-7ece-aa2f-b39ea224556e" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-7ece-aa2f-b39ea224556e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-779b-925e-a8b5b6766d4c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a014-7ece-aa2f-b39ea224556e" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-779b-925e-a8b5b6766d4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a014-7d31-bd29-7e21941bfdac" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a014-779b-925e-a8b5b6766d4c" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a014-7d31-bd29-7e21941bfdac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a014-7116-9845-7f29b3d31fd1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a014-7116-9845-7f29b3d31fd1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019ffbb6-a014-7a1a-bf02-13c1e0ebd71c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_Dividends_019ffbb6-a014-7a1a-bf02-13c1e0ebd71c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_019ffbb6-a014-7f21-b3af-fa7e4c99ce96" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_DividendIncomeOperating_019ffbb6-a014-7f21-b3af-fa7e4c99ce96" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a014-7ce5-9e38-601034b7bb1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a014-7ce5-9e38-601034b7bb1d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-a014-7909-9474-a02fdf3b6bab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-a014-7909-9474-a02fdf3b6bab" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_InterestEarningAssetsAverageYield_019ffbb6-a014-71a7-802d-88b54589f5f1" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_InterestEarningAssetsAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_srt_InterestEarningAssetsAverageYield_019ffbb6-a014-71a7-802d-88b54589f5f1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_019ffbb6-a014-7403-aa16-1a358c51b21b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_LineOfCredit_019ffbb6-a014-7403-aa16-1a358c51b21b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromDispositionOfInvestmentOperatingActivity_019ffbb6-a014-731c-a571-1d8264ea753a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromDispositionOfInvestmentOperatingActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_ProceedsFromDispositionOfInvestmentOperatingActivity_019ffbb6-a014-731c-a571-1d8264ea753a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfInvestments_019ffbb6-a014-7463-bdf4-c57da23f0f80" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnSaleOfInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_GainLossOnSaleOfInvestments_019ffbb6-a014-7463-bdf4-c57da23f0f80" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivables_019ffbb6-a014-7847-b93a-8678c2c5cd0c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a014-71cc-b469-68117dc56aba" xlink:to="loc_us-gaap_OtherReceivables_019ffbb6-a014-7847-b93a-8678c2c5cd0c" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofIndustryCompositionofInvestmentatFairValueDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofIndustryCompositionofInvestmentatFairValueDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofIndustryCompositionofInvestmentatFairValueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-75f9-9620-0b980b2569ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7347-b6fd-f4d0d95092f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-75f9-9620-0b980b2569ec" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7347-b6fd-f4d0d95092f1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-a014-7b94-94ad-b9071eccf1ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesByIndustryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7347-b6fd-f4d0d95092f1" xlink:to="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-a014-7b94-94ad-b9071eccf1ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7b94-94ad-b9071eccf1ac_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-a014-7b94-94ad-b9071eccf1ac" xlink:to="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7b94-94ad-b9071eccf1ac_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesIndustryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EquitySecuritiesByIndustryAxis_019ffbb6-a014-7b94-94ad-b9071eccf1ac" xlink:to="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AerospaceAndDefenseMember_019ffbb6-a014-74ea-8468-646607f3efe7" xlink:href="bbdc-20260930.xsd#bbdc_AerospaceAndDefenseMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_AerospaceAndDefenseMember_019ffbb6-a014-74ea-8468-646607f3efe7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AutomotiveSectorMember_019ffbb6-a014-7a7c-abed-04b4cbc0ec05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AutomotiveSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_us-gaap_AutomotiveSectorMember_019ffbb6-a014-7a7c-abed-04b4cbc0ec05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BankingFinanceInsuranceAndRealEstateMember_019ffbb6-a014-7bfc-9700-f1dbaea94449" xlink:href="bbdc-20260930.xsd#bbdc_BankingFinanceInsuranceAndRealEstateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_BankingFinanceInsuranceAndRealEstateMember_019ffbb6-a014-7bfc-9700-f1dbaea94449" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BeverageFoodAndTobaccoMember_019ffbb6-a014-7544-a7d1-6d8667f83f19" xlink:href="bbdc-20260930.xsd#bbdc_BeverageFoodAndTobaccoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_BeverageFoodAndTobaccoMember_019ffbb6-a014-7544-a7d1-6d8667f83f19" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CapitalEquipmentMember_019ffbb6-a014-79e3-96d5-bde59100ad00" xlink:href="bbdc-20260930.xsd#bbdc_CapitalEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_CapitalEquipmentMember_019ffbb6-a014-79e3-96d5-bde59100ad00" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ChemicalsPlasticsAndRubberMember_019ffbb6-a014-7c7d-be8f-c7cd4320f46b" xlink:href="bbdc-20260930.xsd#bbdc_ChemicalsPlasticsAndRubberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_ChemicalsPlasticsAndRubberMember_019ffbb6-a014-7c7d-be8f-c7cd4320f46b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ConstructionAndBuildingMember_019ffbb6-a014-74d5-a9ce-3fc10a29bd03" xlink:href="bbdc-20260930.xsd#bbdc_ConstructionAndBuildingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_ConstructionAndBuildingMember_019ffbb6-a014-74d5-a9ce-3fc10a29bd03" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ConsumerGoodsDurableMember_019ffbb6-a014-764f-b0f0-ed5317355c2c" xlink:href="bbdc-20260930.xsd#bbdc_ConsumerGoodsDurableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_ConsumerGoodsDurableMember_019ffbb6-a014-764f-b0f0-ed5317355c2c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ConsumerGoodsNonDurableMember_019ffbb6-a014-77a6-98c1-6f73a08bbc23" xlink:href="bbdc-20260930.xsd#bbdc_ConsumerGoodsNonDurableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_ConsumerGoodsNonDurableMember_019ffbb6-a014-77a6-98c1-6f73a08bbc23" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ContainersPackagingAndGlassMember_019ffbb6-a014-79f5-a759-f9b09911e07c" xlink:href="bbdc-20260930.xsd#bbdc_ContainersPackagingAndGlassMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_ContainersPackagingAndGlassMember_019ffbb6-a014-79f5-a759-f9b09911e07c" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnergyElectricityMember_019ffbb6-a014-7621-8a10-aff083f8929f" xlink:href="bbdc-20260930.xsd#bbdc_EnergyElectricityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_EnergyElectricityMember_019ffbb6-a014-7621-8a10-aff083f8929f" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnergyOilAndGasMember_019ffbb6-a014-77fe-93c7-deef6bb631d7" xlink:href="bbdc-20260930.xsd#bbdc_EnergyOilAndGasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_EnergyOilAndGasMember_019ffbb6-a014-77fe-93c7-deef6bb631d7" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EnvironmentalIndustriesMember_019ffbb6-a014-763e-90b4-39fb01af1ef7" xlink:href="bbdc-20260930.xsd#bbdc_EnvironmentalIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_EnvironmentalIndustriesMember_019ffbb6-a014-763e-90b4-39fb01af1ef7" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ForestProductsPaperMember_019ffbb6-a014-7979-8a4f-bb364256abbc" xlink:href="bbdc-20260930.xsd#bbdc_ForestProductsPaperMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_ForestProductsPaperMember_019ffbb6-a014-7979-8a4f-bb364256abbc" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HealthcarePharmaceuticalsMember_019ffbb6-a014-7c48-b770-458932df4123" xlink:href="bbdc-20260930.xsd#bbdc_HealthcarePharmaceuticalsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_HealthcarePharmaceuticalsMember_019ffbb6-a014-7c48-b770-458932df4123" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HighTechIndustriesMember_019ffbb6-a014-786a-9b9e-4068157b7abe" xlink:href="bbdc-20260930.xsd#bbdc_HighTechIndustriesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_HighTechIndustriesMember_019ffbb6-a014-786a-9b9e-4068157b7abe" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_HotelGamingAndLeisureMember_019ffbb6-a014-78be-827c-2bc72d77dd07" xlink:href="bbdc-20260930.xsd#bbdc_HotelGamingAndLeisureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_HotelGamingAndLeisureMember_019ffbb6-a014-78be-827c-2bc72d77dd07" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentFundsAndVehiclesMember_019ffbb6-a014-7607-8c3e-2e3d14af6b84" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentFundsAndVehiclesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_InvestmentFundsAndVehiclesMember_019ffbb6-a014-7607-8c3e-2e3d14af6b84" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaAdvertisingPrintingAndPublishingMember_019ffbb6-a014-7092-ad30-417ab0e2429f" xlink:href="bbdc-20260930.xsd#bbdc_MediaAdvertisingPrintingAndPublishingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_MediaAdvertisingPrintingAndPublishingMember_019ffbb6-a014-7092-ad30-417ab0e2429f" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaBroadcastingAndSubscriptionMember_019ffbb6-a0bc-709a-bf0f-50c12b958ada" xlink:href="bbdc-20260930.xsd#bbdc_MediaBroadcastingAndSubscriptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_MediaBroadcastingAndSubscriptionMember_019ffbb6-a0bc-709a-bf0f-50c12b958ada" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MediaDiversifiedAndProductionMember_019ffbb6-a0bc-77a9-9fd2-b26de9422995" xlink:href="bbdc-20260930.xsd#bbdc_MediaDiversifiedAndProductionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_MediaDiversifiedAndProductionMember_019ffbb6-a0bc-77a9-9fd2-b26de9422995" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MetalsAndMiningMember_019ffbb6-a0bc-72eb-b036-d5895c1be8ac" xlink:href="bbdc-20260930.xsd#bbdc_MetalsAndMiningMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_MetalsAndMiningMember_019ffbb6-a0bc-72eb-b036-d5895c1be8ac" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetailSectorMember_019ffbb6-a0bc-7943-bf40-401e6934c4a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetailSectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_us-gaap_RetailSectorMember_019ffbb6-a0bc-7943-bf40-401e6934c4a6" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ServicesBusinessMember_019ffbb6-a0bc-7d70-a499-cfe04ab48cb7" xlink:href="bbdc-20260930.xsd#bbdc_ServicesBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_ServicesBusinessMember_019ffbb6-a0bc-7d70-a499-cfe04ab48cb7" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ServicesConsumerMember_019ffbb6-a0bc-730d-ae71-508b36ad82b7" xlink:href="bbdc-20260930.xsd#bbdc_ServicesConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_ServicesConsumerMember_019ffbb6-a0bc-730d-ae71-508b36ad82b7" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TelecommunicationsMember_019ffbb6-a0bc-7321-9c17-5117771dc3cb" xlink:href="bbdc-20260930.xsd#bbdc_TelecommunicationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_TelecommunicationsMember_019ffbb6-a0bc-7321-9c17-5117771dc3cb" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TransportationCargoMember_019ffbb6-a0bc-7798-a40e-c5ba3d9cb068" xlink:href="bbdc-20260930.xsd#bbdc_TransportationCargoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_TransportationCargoMember_019ffbb6-a0bc-7798-a40e-c5ba3d9cb068" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_TransportationConsumerMember_019ffbb6-a0bc-743d-ae96-ce3019867c39" xlink:href="bbdc-20260930.xsd#bbdc_TransportationConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_TransportationConsumerMember_019ffbb6-a0bc-743d-ae96-ce3019867c39" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_UtilitiesElectricMember_019ffbb6-a0bc-70f9-bf48-9a593c426fdc" xlink:href="bbdc-20260930.xsd#bbdc_UtilitiesElectricMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_UtilitiesElectricMember_019ffbb6-a0bc-70f9-bf48-9a593c426fdc" xlink:type="arc" order="28"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_UtilitiesOilAndGasMember_019ffbb6-a0bc-75ae-8b67-cd046e8dae9c" xlink:href="bbdc-20260930.xsd#bbdc_UtilitiesOilAndGasMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquitySecuritiesIndustryMember_019ffbb6-a014-7c6a-8c01-34fa5667c9cd" xlink:to="loc_bbdc_UtilitiesOilAndGasMember_019ffbb6-a0bc-75ae-8b67-cd046e8dae9c" xlink:type="arc" order="29"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-7f5a-b300-2995785e80a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7347-b6fd-f4d0d95092f1" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-7f5a-b300-2995785e80a1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7f5a-b300-2995785e80a1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-7f5a-b300-2995785e80a1" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7f5a-b300-2995785e80a1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-71e0-b778-f71763c7c122" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-7f5a-b300-2995785e80a1" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-71e0-b778-f71763c7c122" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedAtFairValueMember_019ffbb6-a0bc-7899-a838-907fd6204c07" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedAtFairValueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-71e0-b778-f71763c7c122" xlink:to="loc_bbdc_InvestmentOwnedAtFairValueMember_019ffbb6-a0bc-7899-a838-907fd6204c07" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7554-83e8-f1a25fc820d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7347-b6fd-f4d0d95092f1" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7554-83e8-f1a25fc820d4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7554-83e8-f1a25fc820d4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7554-83e8-f1a25fc820d4" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7554-83e8-f1a25fc820d4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7a03-938f-2003b1b0dba8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7554-83e8-f1a25fc820d4" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7a03-938f-2003b1b0dba8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_IndustryConcentrationRiskMember_019ffbb6-a0bc-7637-89a2-64dff6fb6a73" xlink:href="bbdc-20260930.xsd#bbdc_IndustryConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7a03-938f-2003b1b0dba8" xlink:to="loc_bbdc_IndustryConcentrationRiskMember_019ffbb6-a0bc-7637-89a2-64dff6fb6a73" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7699-8c08-b9c2da84e4f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7347-b6fd-f4d0d95092f1" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7699-8c08-b9c2da84e4f2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7699-8c08-b9c2da84e4f2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7699-8c08-b9c2da84e4f2" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7699-8c08-b9c2da84e4f2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7787-8ce6-cf20372a4a10" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7699-8c08-b9c2da84e4f2" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7787-8ce6-cf20372a4a10" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a0bc-7675-a3ec-d3a7329e1ede" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7787-8ce6-cf20372a4a10" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a0bc-7675-a3ec-d3a7329e1ede" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraJVMember_01a0858c-87eb-7614-a851-e894e0247b6d" xlink:href="bbdc-20260930.xsd#bbdc_SierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7787-8ce6-cf20372a4a10" xlink:to="loc_bbdc_SierraJVMember_01a0858c-87eb-7614-a851-e894e0247b6d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-71b9-8c11-db108cd516fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a014-7347-b6fd-f4d0d95092f1" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-71b9-8c11-db108cd516fc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-71b9-8c11-db108cd516fc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-71b9-8c11-db108cd516fc" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-71b9-8c11-db108cd516fc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7df0-b826-5b5438143f65" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-71b9-8c11-db108cd516fc" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7df0-b826-5b5438143f65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember_019ffbb6-a0bc-79b9-95ed-b1d94b4ef541" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7df0-b826-5b5438143f65" xlink:to="loc_bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember_019ffbb6-a0bc-79b9-95ed-b1d94b4ef541" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7fbd-8017-482f63e1cf62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-75f9-9620-0b980b2569ec" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7fbd-8017-482f63e1cf62" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019ffbb6-a0bc-7f77-9141-98903a802dfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-75f9-9620-0b980b2569ec" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019ffbb6-a0bc-7f77-9141-98903a802dfe" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofGeographicCompositionofInvestmentatFairValueDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofGeographicCompositionofInvestmentatFairValueDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofGeographicCompositionofInvestmentatFairValueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-773f-8fce-5c7b013f639c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dcc-b5cd-47153b9652ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-773f-8fce-5c7b013f639c" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dcc-b5cd-47153b9652ec" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_019ffbb6-a0bc-71ad-be6a-357812ae6163" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dcc-b5cd-47153b9652ec" xlink:to="loc_srt_StatementGeographicalAxis_019ffbb6-a0bc-71ad-be6a-357812ae6163" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-71ad-be6a-357812ae6163_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_019ffbb6-a0bc-71ad-be6a-357812ae6163" xlink:to="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-71ad-be6a-357812ae6163_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_019ffbb6-a0bc-71ad-be6a-357812ae6163" xlink:to="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_AU_019ffbb6-a0bc-723d-bd16-ad9867450468" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_AU"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_AU_019ffbb6-a0bc-723d-bd16-ad9867450468" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_AT_019ffbb6-a0bc-757f-b62b-1d94e3c9e1c8" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_AT"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_AT_019ffbb6-a0bc-757f-b62b-1d94e3c9e1c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_BE_019ffbb6-a0bc-7b2f-815e-a9a889c947d5" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_BE"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_BE_019ffbb6-a0bc-7b2f-815e-a9a889c947d5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_019ffbb6-a0bc-7800-b66f-705090c986d8" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_CA_019ffbb6-a0bc-7800-b66f-705090c986d8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_FR_019ffbb6-a0bc-75e7-b7a8-ae4d1f24af49" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_FR"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_FR_019ffbb6-a0bc-75e7-b7a8-ae4d1f24af49" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_DE_019ffbb6-a0bc-7d65-9d05-1800ebb24c59" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_DE"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_DE_019ffbb6-a0bc-7d65-9d05-1800ebb24c59" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_HK_019ffbb6-a0bc-76ba-aeec-5da549833361" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_HK"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_HK_019ffbb6-a0bc-76ba-aeec-5da549833361" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_IE_019ffbb6-a0bc-7340-b227-89b370dff457" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_IE"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_IE_019ffbb6-a0bc-7340-b227-89b370dff457" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_LU_019ffbb6-a0bc-7d1e-b6a1-da2123f189a4" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_LU"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_LU_019ffbb6-a0bc-7d1e-b6a1-da2123f189a4" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_NL_019ffbb6-a0bc-7979-bf75-34d99b5a8917" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_NL"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_NL_019ffbb6-a0bc-7979-bf75-34d99b5a8917" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_SG_019ffbb6-a0bc-76a3-a487-cdbf5bbf80ff" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_SG"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_SG_019ffbb6-a0bc-76a3-a487-cdbf5bbf80ff" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_ES_019ffbb6-a0bc-7a55-8354-855f352f6e3e" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_ES"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_ES_019ffbb6-a0bc-7a55-8354-855f352f6e3e" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_GB_019ffbb6-a0bc-7bb9-865a-bf1cb345e8a6" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_GB"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_GB_019ffbb6-a0bc-7bb9-865a-bf1cb345e8a6" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_019ffbb6-a0bc-77e4-be6e-d393dc1921f6" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_019ffbb6-a0bc-7851-9f47-7baa388c09c0" xlink:to="loc_country_US_019ffbb6-a0bc-77e4-be6e-d393dc1921f6" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-78e7-9a04-e204687a416a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dcc-b5cd-47153b9652ec" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-78e7-9a04-e204687a416a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-78e7-9a04-e204687a416a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-78e7-9a04-e204687a416a" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-78e7-9a04-e204687a416a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7614-9421-2306ac72f1eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-78e7-9a04-e204687a416a" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7614-9421-2306ac72f1eb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a0bc-7f9a-b74d-78b9f5546d23" xlink:href="bbdc-20260930.xsd#bbdc_JocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7614-9421-2306ac72f1eb" xlink:to="loc_bbdc_JocasseePartnersLLCMember_019ffbb6-a0bc-7f9a-b74d-78b9f5546d23" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-7dcd-aba5-51dbd27ab495" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dcc-b5cd-47153b9652ec" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-7dcd-aba5-51dbd27ab495" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7dcd-aba5-51dbd27ab495_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-7dcd-aba5-51dbd27ab495" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7dcd-aba5-51dbd27ab495_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7d02-9380-45ab90b5a5ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-7dcd-aba5-51dbd27ab495" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7d02-9380-45ab90b5a5ca" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedAtFairValueMember_019ffbb6-a0bc-7e5c-88a0-077329753221" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedAtFairValueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7d02-9380-45ab90b5a5ca" xlink:to="loc_bbdc_InvestmentOwnedAtFairValueMember_019ffbb6-a0bc-7e5c-88a0-077329753221" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7fe2-a27d-3a22412f9194" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dcc-b5cd-47153b9652ec" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7fe2-a27d-3a22412f9194" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7fe2-a27d-3a22412f9194_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7fe2-a27d-3a22412f9194" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7fe2-a27d-3a22412f9194_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7694-9540-26c82e5d1e8c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7fe2-a27d-3a22412f9194" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7694-9540-26c82e5d1e8c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeographicConcentrationRiskMember_019ffbb6-a0bc-74ef-9f4c-c9913ec1acdc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeographicConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7694-9540-26c82e5d1e8c" xlink:to="loc_us-gaap_GeographicConcentrationRiskMember_019ffbb6-a0bc-74ef-9f4c-c9913ec1acdc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7a90-95be-c55dd9e2c5cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dcc-b5cd-47153b9652ec" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7a90-95be-c55dd9e2c5cb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7a90-95be-c55dd9e2c5cb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7a90-95be-c55dd9e2c5cb" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7a90-95be-c55dd9e2c5cb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7cc6-8cd3-6c72dae5d977" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7a90-95be-c55dd9e2c5cb" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7cc6-8cd3-6c72dae5d977" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember_019ffbb6-a0bc-71a5-8547-dd522d43ba20" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7cc6-8cd3-6c72dae5d977" xlink:to="loc_bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember_019ffbb6-a0bc-71a5-8547-dd522d43ba20" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7175-af2c-51b99e8cea03" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-773f-8fce-5c7b013f639c" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7175-af2c-51b99e8cea03" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019ffbb6-a0bc-7998-af43-1d9d63850b1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-773f-8fce-5c7b013f639c" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019ffbb6-a0bc-7998-af43-1d9d63850b1d" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofContributedCapitalandUnfundedCommitmentsDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofContributedCapitalandUnfundedCommitmentsDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofContributedCapitalandUnfundedCommitmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-71aa-bd1a-952caa0645fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-71aa-bd1a-952caa0645fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMembersOfJocasseePartnersLLCMember_019ffbb6-a0bc-7387-b1bb-b75a8836c9ae" xlink:href="bbdc-20260930.xsd#bbdc_AllMembersOfJocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:to="loc_bbdc_AllMembersOfJocasseePartnersLLCMember_019ffbb6-a0bc-7387-b1bb-b75a8836c9ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMembersOfThompsonRiversLLCMember_019ffbb6-a0bc-7df3-9aed-4c8c6ebcd054" xlink:href="bbdc-20260930.xsd#bbdc_AllMembersOfThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:to="loc_bbdc_AllMembersOfThompsonRiversLLCMember_019ffbb6-a0bc-7df3-9aed-4c8c6ebcd054" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7d4c-a04c-c988368abe5c" xlink:href="bbdc-20260930.xsd#bbdc_AllMemberOfWaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:to="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7d4c-a04c-c988368abe5c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a0bc-7fc8-9948-c4bea452b563" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a0bc-7fc8-9948-c4bea452b563" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7fc8-9948-c4bea452b563_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a0bc-7fc8-9948-c4bea452b563" xlink:to="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7fc8-9948-c4bea452b563_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7654-9d92-47aa657ae19c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a0bc-7fc8-9948-c4bea452b563" xlink:to="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7654-9d92-47aa657ae19c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AffiliatedEntityMember_019ffbb6-a0bc-7703-969d-8acd5bb0ed94" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AffiliatedEntityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7654-9d92-47aa657ae19c" xlink:to="loc_srt_AffiliatedEntityMember_019ffbb6-a0bc-7703-969d-8acd5bb0ed94" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7f02-97a1-9222a7db177c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7f02-97a1-9222a7db177c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-7dae-ace6-1cc90c22ad3e" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7f02-97a1-9222a7db177c" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-7dae-ace6-1cc90c22ad3e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-7a2a-9707-53f47e1a0183" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7f02-97a1-9222a7db177c" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-7a2a-9707-53f47e1a0183" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-79ad-8de3-0ec64717174f" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-79ad-8de3-0ec64717174f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7e4b-9a2a-886f6ab19405" xlink:href="bbdc-20260930.xsd#bbdc_AllMemberOfWaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-79ad-8de3-0ec64717174f" xlink:to="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7e4b-9a2a-886f6ab19405" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-7586-8710-aa5f4fff1f34" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyAccumulatedContributedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-7586-8710-aa5f4fff1f34" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a0bc-70c9-aefa-261be8864aa5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a0bc-70c9-aefa-261be8864aa5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyDividendReinvestment_019ffbb6-a0bc-7422-a49d-6b60c97e560e" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyDividendReinvestment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_bbdc_InvestmentCompanyDividendReinvestment_019ffbb6-a0bc-7422-a49d-6b60c97e560e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyCommittedCapital_019ffbb6-a0bc-77e2-a6a0-d3c82b832bd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyCommittedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_us-gaap_InvestmentCompanyCommittedCapital_019ffbb6-a0bc-77e2-a6a0-d3c82b832bd3" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofContributedCapitalandUnfundedCommitmentsDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofContributedCapitalandUnfundedCommitmentsDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofContributedCapitalandUnfundedCommitmentsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7334-a29e-16d09ceeb6c1" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMembersOfJocasseePartnersLLCMember_019ffbb6-a0bc-7387-b1bb-b75a8836c9ae" xlink:href="bbdc-20260930.xsd#bbdc_AllMembersOfJocasseePartnersLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:to="loc_bbdc_AllMembersOfJocasseePartnersLLCMember_019ffbb6-a0bc-7387-b1bb-b75a8836c9ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMembersOfThompsonRiversLLCMember_019ffbb6-a0bc-7df3-9aed-4c8c6ebcd054" xlink:href="bbdc-20260930.xsd#bbdc_AllMembersOfThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:to="loc_bbdc_AllMembersOfThompsonRiversLLCMember_019ffbb6-a0bc-7df3-9aed-4c8c6ebcd054" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7d4c-a04c-c988368abe5c" xlink:href="bbdc-20260930.xsd#bbdc_AllMemberOfWaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7686-a133-bdf10fe59877" xlink:to="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7d4c-a04c-c988368abe5c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a0bc-7fc8-9948-c4bea452b563" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a0bc-7fc8-9948-c4bea452b563" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7fc8-9948-c4bea452b563_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a0bc-7fc8-9948-c4bea452b563" xlink:to="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7fc8-9948-c4bea452b563_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7654-9d92-47aa657ae19c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019ffbb6-a0bc-7fc8-9948-c4bea452b563" xlink:to="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7654-9d92-47aa657ae19c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AffiliatedEntityMember_019ffbb6-a0bc-7703-969d-8acd5bb0ed94" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AffiliatedEntityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019ffbb6-a0bc-7654-9d92-47aa657ae19c" xlink:to="loc_srt_AffiliatedEntityMember_019ffbb6-a0bc-7703-969d-8acd5bb0ed94" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7f02-97a1-9222a7db177c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7721-b4de-8f4e66fc6ea7" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7f02-97a1-9222a7db177c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-7dae-ace6-1cc90c22ad3e" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7f02-97a1-9222a7db177c" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-7dae-ace6-1cc90c22ad3e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-7a2a-9707-53f47e1a0183" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7f02-97a1-9222a7db177c" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-7a2a-9707-53f47e1a0183" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70bb-af75-8c9a9cac8f52" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-79ad-8de3-0ec64717174f" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-71e4-9dd9-8f6613b2bced" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-79ad-8de3-0ec64717174f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7e4b-9a2a-886f6ab19405" xlink:href="bbdc-20260930.xsd#bbdc_AllMemberOfWaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-79ad-8de3-0ec64717174f" xlink:to="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7e4b-9a2a-886f6ab19405" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-7586-8710-aa5f4fff1f34" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyAccumulatedContributedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-7586-8710-aa5f4fff1f34" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a0bc-70c9-aefa-261be8864aa5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a0bc-70c9-aefa-261be8864aa5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyDividendReinvestment_019ffbb6-a0bc-7422-a49d-6b60c97e560e" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyDividendReinvestment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_bbdc_InvestmentCompanyDividendReinvestment_019ffbb6-a0bc-7422-a49d-6b60c97e560e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyCommittedCapital_019ffbb6-a0bc-77e2-a6a0-d3c82b832bd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyCommittedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-77a1-950f-4d9b68d7d7da" xlink:to="loc_us-gaap_InvestmentCompanyCommittedCapital_019ffbb6-a0bc-77e2-a6a0-d3c82b832bd3" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSThompsonRiversLLCDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSThompsonRiversLLCDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSThompsonRiversLLCDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-71ea-9e8d-f2c7eff7615b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-71ea-9e8d-f2c7eff7615b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a0bc-79b8-9127-e4ec8a689f28" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a0bc-79b8-9127-e4ec8a689f28" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-79b8-9127-e4ec8a689f28_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-79b8-9127-e4ec8a689f28" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-79b8-9127-e4ec8a689f28_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-7d26-8aed-48a8ab8d51c3" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-79b8-9127-e4ec8a689f28" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-7d26-8aed-48a8ab8d51c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-70e3-ada9-3ce500fabd73" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-7d26-8aed-48a8ab8d51c3" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-70e3-ada9-3ce500fabd73" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7b77-b202-f045c15294d9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7b77-b202-f045c15294d9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7b77-b202-f045c15294d9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7b77-b202-f045c15294d9" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7b77-b202-f045c15294d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7930-ad1f-95870a5be22d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7b77-b202-f045c15294d9" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7930-ad1f-95870a5be22d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-7e49-8535-76d43048b015" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7930-ad1f-95870a5be22d" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-7e49-8535-76d43048b015" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7746-a889-40c3a65663be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7746-a889-40c3a65663be" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7746-a889-40c3a65663be_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7746-a889-40c3a65663be" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7746-a889-40c3a65663be_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-75b6-a793-55030fffdb0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7746-a889-40c3a65663be" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-75b6-a793-55030fffdb0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_GinnieMaeEarlyBuyoutLoansMember_019ffbb6-a0bc-7e8f-bbb1-231129cd9333" xlink:href="bbdc-20260930.xsd#bbdc_GinnieMaeEarlyBuyoutLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-75b6-a793-55030fffdb0a" xlink:to="loc_bbdc_GinnieMaeEarlyBuyoutLoansMember_019ffbb6-a0bc-7e8f-bbb1-231129cd9333" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsMember_019ffbb6-a0bc-7f27-9241-0ee9f2f97041" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-75b6-a793-55030fffdb0a" xlink:to="loc_us-gaap_CashAndCashEquivalentsMember_019ffbb6-a0bc-7f27-9241-0ee9f2f97041" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7989-9abf-69426293a361" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7989-9abf-69426293a361" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7989-9abf-69426293a361_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7989-9abf-69426293a361" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7989-9abf-69426293a361_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d39-8bcf-a73cb4aa4d2a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7989-9abf-69426293a361" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d39-8bcf-a73cb4aa4d2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JPMorganChaseBankMember_019ffbb6-a0bc-75ca-a42c-29542c95ed8c" xlink:href="bbdc-20260930.xsd#bbdc_JPMorganChaseBankMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d39-8bcf-a73cb4aa4d2a" xlink:to="loc_bbdc_JPMorganChaseBankMember_019ffbb6-a0bc-75ca-a42c-29542c95ed8c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BankOfAmericaNAMember_019ffbb6-a0bc-7259-b979-ddd3eae23aa5" xlink:href="bbdc-20260930.xsd#bbdc_BankOfAmericaNAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d39-8bcf-a73cb4aa4d2a" xlink:to="loc_bbdc_BankOfAmericaNAMember_019ffbb6-a0bc-7259-b979-ddd3eae23aa5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-7edb-8975-c7269b2eb271" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyAccumulatedContributedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-7edb-8975-c7269b2eb271" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019ffbb6-a0bc-71b2-91f9-b70ce9f28b43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_Dividends_019ffbb6-a0bc-71b2-91f9-b70ce9f28b43" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-703f-ad42-4b7e16af2b06" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-703f-ad42-4b7e16af2b06" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-7800-baa4-03926fd6d537" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyDistributionsOfRealizedGains"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-7800-baa4-03926fd6d537" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7ad7-b0e1-3e38ad4153ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7ad7-b0e1-3e38ad4153ba" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedOutstandingLoans_019ffbb6-a0bc-7372-9f8a-4a8678872396" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedOutstandingLoans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentOwnedOutstandingLoans_019ffbb6-a0bc-7372-9f8a-4a8678872396" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedAverageUnpaidBalance_019ffbb6-a0bc-73ea-83e8-564d29fa7534" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedAverageUnpaidBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentOwnedAverageUnpaidBalance_019ffbb6-a0bc-73ea-83e8-564d29fa7534" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedWeightedAverageYieldRate_019ffbb6-a0bc-7431-86cd-9ce1cb00a3a4" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedWeightedAverageYieldRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentOwnedWeightedAverageYieldRate_019ffbb6-a0bc-7431-86cd-9ce1cb00a3a4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepurchaseAgreementCounterpartyAmountAtRisk_019ffbb6-a0bc-751d-bb90-1f2c2f1898c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepurchaseAgreementCounterpartyAmountAtRisk"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_RepurchaseAgreementCounterpartyAmountAtRisk_019ffbb6-a0bc-751d-bb90-1f2c2f1898c4" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSThompsonRiversLLCDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSThompsonRiversLLCDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSThompsonRiversLLCDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a0bc-79b8-9127-e4ec8a689f28" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a0bc-79b8-9127-e4ec8a689f28" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-79b8-9127-e4ec8a689f28_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-79b8-9127-e4ec8a689f28" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-79b8-9127-e4ec8a689f28_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-7d26-8aed-48a8ab8d51c3" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-79b8-9127-e4ec8a689f28" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-7d26-8aed-48a8ab8d51c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-70e3-ada9-3ce500fabd73" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-7d26-8aed-48a8ab8d51c3" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-70e3-ada9-3ce500fabd73" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7b77-b202-f045c15294d9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7b77-b202-f045c15294d9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7b77-b202-f045c15294d9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7b77-b202-f045c15294d9" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7b77-b202-f045c15294d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7930-ad1f-95870a5be22d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7b77-b202-f045c15294d9" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7930-ad1f-95870a5be22d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-7e49-8535-76d43048b015" xlink:href="bbdc-20260930.xsd#bbdc_ThompsonRiversLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7930-ad1f-95870a5be22d" xlink:to="loc_bbdc_ThompsonRiversLLCMember_019ffbb6-a0bc-7e49-8535-76d43048b015" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7746-a889-40c3a65663be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7746-a889-40c3a65663be" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7746-a889-40c3a65663be_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7746-a889-40c3a65663be" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7746-a889-40c3a65663be_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-75b6-a793-55030fffdb0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7746-a889-40c3a65663be" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-75b6-a793-55030fffdb0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_GinnieMaeEarlyBuyoutLoansMember_019ffbb6-a0bc-7e8f-bbb1-231129cd9333" xlink:href="bbdc-20260930.xsd#bbdc_GinnieMaeEarlyBuyoutLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-75b6-a793-55030fffdb0a" xlink:to="loc_bbdc_GinnieMaeEarlyBuyoutLoansMember_019ffbb6-a0bc-7e8f-bbb1-231129cd9333" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsMember_019ffbb6-a0bc-7f27-9241-0ee9f2f97041" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-75b6-a793-55030fffdb0a" xlink:to="loc_us-gaap_CashAndCashEquivalentsMember_019ffbb6-a0bc-7f27-9241-0ee9f2f97041" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7989-9abf-69426293a361" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7dc3-9062-071c58ba095b" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7989-9abf-69426293a361" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7989-9abf-69426293a361_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7989-9abf-69426293a361" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7989-9abf-69426293a361_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d39-8bcf-a73cb4aa4d2a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7989-9abf-69426293a361" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d39-8bcf-a73cb4aa4d2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_JPMorganChaseBankMember_019ffbb6-a0bc-75ca-a42c-29542c95ed8c" xlink:href="bbdc-20260930.xsd#bbdc_JPMorganChaseBankMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d39-8bcf-a73cb4aa4d2a" xlink:to="loc_bbdc_JPMorganChaseBankMember_019ffbb6-a0bc-75ca-a42c-29542c95ed8c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BankOfAmericaNAMember_019ffbb6-a0bc-7259-b979-ddd3eae23aa5" xlink:href="bbdc-20260930.xsd#bbdc_BankOfAmericaNAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d39-8bcf-a73cb4aa4d2a" xlink:to="loc_bbdc_BankOfAmericaNAMember_019ffbb6-a0bc-7259-b979-ddd3eae23aa5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-7edb-8975-c7269b2eb271" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyAccumulatedContributedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-7edb-8975-c7269b2eb271" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019ffbb6-a0bc-71b2-91f9-b70ce9f28b43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_Dividends_019ffbb6-a0bc-71b2-91f9-b70ce9f28b43" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-703f-ad42-4b7e16af2b06" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-703f-ad42-4b7e16af2b06" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-7800-baa4-03926fd6d537" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyDistributionsOfRealizedGains"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-7800-baa4-03926fd6d537" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7ad7-b0e1-3e38ad4153ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7ad7-b0e1-3e38ad4153ba" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedOutstandingLoans_019ffbb6-a0bc-7372-9f8a-4a8678872396" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedOutstandingLoans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentOwnedOutstandingLoans_019ffbb6-a0bc-7372-9f8a-4a8678872396" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedAverageUnpaidBalance_019ffbb6-a0bc-73ea-83e8-564d29fa7534" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedAverageUnpaidBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentOwnedAverageUnpaidBalance_019ffbb6-a0bc-73ea-83e8-564d29fa7534" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedWeightedAverageYieldRate_019ffbb6-a0bc-7431-86cd-9ce1cb00a3a4" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedWeightedAverageYieldRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_bbdc_InvestmentOwnedWeightedAverageYieldRate_019ffbb6-a0bc-7431-86cd-9ce1cb00a3a4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepurchaseAgreementCounterpartyAmountAtRisk_019ffbb6-a0bc-751d-bb90-1f2c2f1898c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepurchaseAgreementCounterpartyAmountAtRisk"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7874-a839-951914cd98b4" xlink:to="loc_us-gaap_RepurchaseAgreementCounterpartyAmountAtRisk_019ffbb6-a0bc-751d-bb90-1f2c2f1898c4" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSWaccamawRiverLLCDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSWaccamawRiverLLCDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSWaccamawRiverLLCDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-7ce4-9035-99a88c78bba9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-7ce4-9035-99a88c78bba9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7bee-b151-839c63b23c96" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7bee-b151-839c63b23c96" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-7bee-b151-839c63b23c96_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7bee-b151-839c63b23c96" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-7bee-b151-839c63b23c96_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-701a-a7ba-f435ea739f1a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7bee-b151-839c63b23c96" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-701a-a7ba-f435ea739f1a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7283-915c-acbb95be7866" xlink:href="bbdc-20260930.xsd#bbdc_AllMemberOfWaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-701a-a7ba-f435ea739f1a" xlink:to="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7283-915c-acbb95be7866" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-738c-bf8c-759a3ea0c3a2" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-701a-a7ba-f435ea739f1a" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-738c-bf8c-759a3ea0c3a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-73d0-88d2-377b93941673" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-73d0-88d2-377b93941673" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-73d0-88d2-377b93941673_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-73d0-88d2-377b93941673" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-73d0-88d2-377b93941673_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-71f0-85a8-6eab29f876b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-73d0-88d2-377b93941673" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-71f0-85a8-6eab29f876b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-7466-88cb-144f5c55830b" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-71f0-85a8-6eab29f876b9" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-7466-88cb-144f5c55830b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7703-aa78-763c78ef96a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7703-aa78-763c78ef96a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerLoanMember_019ffbb6-a0bc-7da9-8ca8-216f1830836b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7703-aa78-763c78ef96a6" xlink:to="loc_us-gaap_ConsumerLoanMember_019ffbb6-a0bc-7da9-8ca8-216f1830836b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsMember_019ffbb6-a0bc-7271-af24-8239a693abac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7703-aa78-763c78ef96a6" xlink:to="loc_us-gaap_CashAndCashEquivalentsMember_019ffbb6-a0bc-7271-af24-8239a693abac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-771e-99c1-d8929aa2c617" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyAccumulatedContributedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-771e-99c1-d8929aa2c617" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019ffbb6-a0bc-7418-a260-8405397847c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_us-gaap_Dividends_019ffbb6-a0bc-7418-a260-8405397847c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-74f2-b9e0-fcdf7f19c209" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-74f2-b9e0-fcdf7f19c209" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-769e-948e-951b90d80772" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyDistributionsOfRealizedGains"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-769e-948e-951b90d80772" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7b26-8894-d32364869bfa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7b26-8894-d32364869bfa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedOutstandingLoans_019ffbb6-a0bc-7630-aa04-399d4e690c1a" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedOutstandingLoans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentOwnedOutstandingLoans_019ffbb6-a0bc-7630-aa04-399d4e690c1a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyAverageLoanAmount_019ffbb6-a0bc-7b08-ad3f-72832fd2c599" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyAverageLoanAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentCompanyAverageLoanAmount_019ffbb6-a0bc-7b08-ad3f-72832fd2c599" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyRemainingAverageLifeToMaturity_019ffbb6-a0bc-7e0b-b450-581636adc786" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyRemainingAverageLifeToMaturity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentCompanyRemainingAverageLifeToMaturity_019ffbb6-a0bc-7e0b-b450-581636adc786" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedWeightedAverageYieldRate_019ffbb6-a0bc-716f-84be-5b856629f4ea" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedWeightedAverageYieldRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentOwnedWeightedAverageYieldRate_019ffbb6-a0bc-716f-84be-5b856629f4ea" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSWaccamawRiverLLCDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSWaccamawRiverLLCDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSWaccamawRiverLLCDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7bee-b151-839c63b23c96" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7bee-b151-839c63b23c96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-7bee-b151-839c63b23c96_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7bee-b151-839c63b23c96" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-7bee-b151-839c63b23c96_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-701a-a7ba-f435ea739f1a" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7bee-b151-839c63b23c96" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-701a-a7ba-f435ea739f1a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7283-915c-acbb95be7866" xlink:href="bbdc-20260930.xsd#bbdc_AllMemberOfWaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-701a-a7ba-f435ea739f1a" xlink:to="loc_bbdc_AllMemberOfWaccamawRiverLLCMember_019ffbb6-a0bc-7283-915c-acbb95be7866" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-738c-bf8c-759a3ea0c3a2" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-701a-a7ba-f435ea739f1a" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-738c-bf8c-759a3ea0c3a2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-73d0-88d2-377b93941673" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-73d0-88d2-377b93941673" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-73d0-88d2-377b93941673_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-73d0-88d2-377b93941673" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-73d0-88d2-377b93941673_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-71f0-85a8-6eab29f876b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-73d0-88d2-377b93941673" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-71f0-85a8-6eab29f876b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-7466-88cb-144f5c55830b" xlink:href="bbdc-20260930.xsd#bbdc_WaccamawRiverLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-71f0-85a8-6eab29f876b9" xlink:to="loc_bbdc_WaccamawRiverLLCMember_019ffbb6-a0bc-7466-88cb-144f5c55830b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-773a-ae40-096c473f4b3e" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7703-aa78-763c78ef96a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7dfc-96f7-eb9b13c8199c" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7703-aa78-763c78ef96a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerLoanMember_019ffbb6-a0bc-7da9-8ca8-216f1830836b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7703-aa78-763c78ef96a6" xlink:to="loc_us-gaap_ConsumerLoanMember_019ffbb6-a0bc-7da9-8ca8-216f1830836b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsMember_019ffbb6-a0bc-7271-af24-8239a693abac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7703-aa78-763c78ef96a6" xlink:to="loc_us-gaap_CashAndCashEquivalentsMember_019ffbb6-a0bc-7271-af24-8239a693abac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-771e-99c1-d8929aa2c617" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyAccumulatedContributedCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentCompanyAccumulatedContributedCapital_019ffbb6-a0bc-771e-99c1-d8929aa2c617" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019ffbb6-a0bc-7418-a260-8405397847c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_us-gaap_Dividends_019ffbb6-a0bc-7418-a260-8405397847c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-74f2-b9e0-fcdf7f19c209" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-74f2-b9e0-fcdf7f19c209" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-769e-948e-951b90d80772" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyDistributionsOfRealizedGains"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-769e-948e-951b90d80772" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7b26-8894-d32364869bfa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7b26-8894-d32364869bfa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedOutstandingLoans_019ffbb6-a0bc-7630-aa04-399d4e690c1a" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedOutstandingLoans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentOwnedOutstandingLoans_019ffbb6-a0bc-7630-aa04-399d4e690c1a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyAverageLoanAmount_019ffbb6-a0bc-7b08-ad3f-72832fd2c599" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyAverageLoanAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentCompanyAverageLoanAmount_019ffbb6-a0bc-7b08-ad3f-72832fd2c599" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyRemainingAverageLifeToMaturity_019ffbb6-a0bc-7e0b-b450-581636adc786" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyRemainingAverageLifeToMaturity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentCompanyRemainingAverageLifeToMaturity_019ffbb6-a0bc-7e0b-b450-581636adc786" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedWeightedAverageYieldRate_019ffbb6-a0bc-716f-84be-5b856629f4ea" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedWeightedAverageYieldRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7a72-8554-0427a3356cb2" xlink:to="loc_bbdc_InvestmentOwnedWeightedAverageYieldRate_019ffbb6-a0bc-716f-84be-5b856629f4ea" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSSierraSeniorLoanStrategyJVILLCDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSSierraSeniorLoanStrategyJVILLCDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSSierraSeniorLoanStrategyJVILLCDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7120-9316-eb5b06cf504e" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7120-9316-eb5b06cf504e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-7120-9316-eb5b06cf504e_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7120-9316-eb5b06cf504e" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-7120-9316-eb5b06cf504e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-7df8-900c-e785a6ac5102" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7120-9316-eb5b06cf504e" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-7df8-900c-e785a6ac5102" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMembersOfSierraJVMember_019ffbb6-a0bc-76aa-b03b-b67025610907" xlink:href="bbdc-20260930.xsd#bbdc_AllMembersOfSierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-7df8-900c-e785a6ac5102" xlink:to="loc_bbdc_AllMembersOfSierraJVMember_019ffbb6-a0bc-76aa-b03b-b67025610907" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraJVMember_019ffbb6-a0bc-7caf-8ac1-31b26a4c83ec" xlink:href="bbdc-20260930.xsd#bbdc_SierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-7df8-900c-e785a6ac5102" xlink:to="loc_bbdc_SierraJVMember_019ffbb6-a0bc-7caf-8ac1-31b26a4c83ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7d9f-88c9-e24cc5247075" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7d9f-88c9-e24cc5247075" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d9f-88c9-e24cc5247075_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7d9f-88c9-e24cc5247075" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d9f-88c9-e24cc5247075_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-703f-85c9-41cdf8699ca4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7d9f-88c9-e24cc5247075" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-703f-85c9-41cdf8699ca4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MassMutualAscendLifeInsuranceCompanyMember_019ffbb6-a0bc-7c57-a6d6-c6131934261e" xlink:href="bbdc-20260930.xsd#bbdc_MassMutualAscendLifeInsuranceCompanyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-703f-85c9-41cdf8699ca4" xlink:to="loc_bbdc_MassMutualAscendLifeInsuranceCompanyMember_019ffbb6-a0bc-7c57-a6d6-c6131934261e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7622-9f6d-03069584314c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7622-9f6d-03069584314c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7622-9f6d-03069584314c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7622-9f6d-03069584314c" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7622-9f6d-03069584314c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7226-97b1-d9ac32a2bb58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7622-9f6d-03069584314c" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7226-97b1-d9ac32a2bb58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMembersOfSierraJVMember_019ffbb6-a0bc-7892-a274-752a15dfec46" xlink:href="bbdc-20260930.xsd#bbdc_AllMembersOfSierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7226-97b1-d9ac32a2bb58" xlink:to="loc_bbdc_AllMembersOfSierraJVMember_019ffbb6-a0bc-7892-a274-752a15dfec46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraJVMember_019ffbb6-a0bc-7aff-b049-8201adb8062e" xlink:href="bbdc-20260930.xsd#bbdc_SierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7226-97b1-d9ac32a2bb58" xlink:to="loc_bbdc_SierraJVMember_019ffbb6-a0bc-7aff-b049-8201adb8062e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-79f9-9ce1-e57a7f9b2118" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-79f9-9ce1-e57a7f9b2118" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyNumberOfMembersContributed_019ffbb6-a0bc-7b4b-b080-6383dd75d6f2" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyNumberOfMembersContributed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_bbdc_InvestmentCompanyNumberOfMembersContributed_019ffbb6-a0bc-7b4b-b080-6383dd75d6f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019ffbb6-a0bc-73ad-9ea5-45e786bef068" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_Dividends_019ffbb6-a0bc-73ad-9ea5-45e786bef068" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-7731-9fa2-954379bd6ae1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-7731-9fa2-954379bd6ae1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-706a-85ca-7976939dc5c8" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyDistributionsOfRealizedGains"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-706a-85ca-7976939dc5c8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7459-a98e-0ea8235a3a46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7459-a98e-0ea8235a3a46" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-a0bc-7582-b761-29e8292e6514" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-a0bc-7582-b761-29e8292e6514" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedWeightedAverageYield_019ffbb6-a0bc-758c-ad93-fbbf28d072bd" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedWeightedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_bbdc_InvestmentOwnedWeightedAverageYield_019ffbb6-a0bc-758c-ad93-fbbf28d072bd" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSSierraSeniorLoanStrategyJVILLCDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSSierraSeniorLoanStrategyJVILLCDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSSierraSeniorLoanStrategyJVILLCDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7120-9316-eb5b06cf504e" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:to="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7120-9316-eb5b06cf504e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-7120-9316-eb5b06cf504e_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7120-9316-eb5b06cf504e" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-7120-9316-eb5b06cf504e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_019ffbb6-a0bc-7df8-900c-e785a6ac5102" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_019ffbb6-a0bc-7120-9316-eb5b06cf504e" xlink:to="loc_dei_EntityDomain_019ffbb6-a0bc-7df8-900c-e785a6ac5102" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMembersOfSierraJVMember_019ffbb6-a0bc-76aa-b03b-b67025610907" xlink:href="bbdc-20260930.xsd#bbdc_AllMembersOfSierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-7df8-900c-e785a6ac5102" xlink:to="loc_bbdc_AllMembersOfSierraJVMember_019ffbb6-a0bc-76aa-b03b-b67025610907" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraJVMember_019ffbb6-a0bc-7caf-8ac1-31b26a4c83ec" xlink:href="bbdc-20260930.xsd#bbdc_SierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_019ffbb6-a0bc-7df8-900c-e785a6ac5102" xlink:to="loc_bbdc_SierraJVMember_019ffbb6-a0bc-7caf-8ac1-31b26a4c83ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7d9f-88c9-e24cc5247075" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7d9f-88c9-e24cc5247075" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d9f-88c9-e24cc5247075_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7d9f-88c9-e24cc5247075" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7d9f-88c9-e24cc5247075_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-703f-85c9-41cdf8699ca4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7d9f-88c9-e24cc5247075" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-703f-85c9-41cdf8699ca4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MassMutualAscendLifeInsuranceCompanyMember_019ffbb6-a0bc-7c57-a6d6-c6131934261e" xlink:href="bbdc-20260930.xsd#bbdc_MassMutualAscendLifeInsuranceCompanyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-703f-85c9-41cdf8699ca4" xlink:to="loc_bbdc_MassMutualAscendLifeInsuranceCompanyMember_019ffbb6-a0bc-7c57-a6d6-c6131934261e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7622-9f6d-03069584314c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7e7a-ab99-a7f4df7b5534" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7622-9f6d-03069584314c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7622-9f6d-03069584314c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7622-9f6d-03069584314c" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7622-9f6d-03069584314c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7226-97b1-d9ac32a2bb58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_019ffbb6-a0bc-7622-9f6d-03069584314c" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7226-97b1-d9ac32a2bb58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AllMembersOfSierraJVMember_019ffbb6-a0bc-7892-a274-752a15dfec46" xlink:href="bbdc-20260930.xsd#bbdc_AllMembersOfSierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7226-97b1-d9ac32a2bb58" xlink:to="loc_bbdc_AllMembersOfSierraJVMember_019ffbb6-a0bc-7892-a274-752a15dfec46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraJVMember_019ffbb6-a0bc-7aff-b049-8201adb8062e" xlink:href="bbdc-20260930.xsd#bbdc_SierraJVMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_019ffbb6-a0bc-7226-97b1-d9ac32a2bb58" xlink:to="loc_bbdc_SierraJVMember_019ffbb6-a0bc-7aff-b049-8201adb8062e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyNumberOfMembersContributed_019ffbb6-a0bc-7b4b-b080-6383dd75d6f2" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyNumberOfMembersContributed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_bbdc_InvestmentCompanyNumberOfMembersContributed_019ffbb6-a0bc-7b4b-b080-6383dd75d6f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019ffbb6-a0bc-73ad-9ea5-45e786bef068" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_Dividends_019ffbb6-a0bc-73ad-9ea5-45e786bef068" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-7731-9fa2-954379bd6ae1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_DividendIncomeOperating_019ffbb6-a0bc-7731-9fa2-954379bd6ae1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-706a-85ca-7976939dc5c8" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentCompanyDistributionsOfRealizedGains"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_bbdc_InvestmentCompanyDistributionsOfRealizedGains_019ffbb6-a0bc-706a-85ca-7976939dc5c8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7459-a98e-0ea8235a3a46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-7459-a98e-0ea8235a3a46" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-a0bc-7582-b761-29e8292e6514" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019ffbb6-a0bc-7582-b761-29e8292e6514" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedWeightedAverageYield_019ffbb6-a0bc-758c-ad93-fbbf28d072bd" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedWeightedAverageYield"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7055-bff7-406c358652a3" xlink:to="loc_bbdc_InvestmentOwnedWeightedAverageYield_019ffbb6-a0bc-758c-ad93-fbbf28d072bd" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSEclipseBusinessCapitalHoldingsLLCDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSEclipseBusinessCapitalHoldingsLLCDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSEclipseBusinessCapitalHoldingsLLCDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-78a0-8456-ce4a40830c6e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-78a0-8456-ce4a40830c6e" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a12077-8052-794b-b3de-14956117e4c8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:to="loc_srt_RangeAxis_01a12077-8052-794b-b3de-14956117e4c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a12077-8052-794b-b3de-14956117e4c8_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a12077-8052-794b-b3de-14956117e4c8" xlink:to="loc_srt_RangeMember_01a12077-8052-794b-b3de-14956117e4c8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a12077-8052-7384-ad05-02190fef7950" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a12077-8052-794b-b3de-14956117e4c8" xlink:to="loc_srt_RangeMember_01a12077-8052-7384-ad05-02190fef7950" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a12077-8052-7928-83d6-b7bfa2b022ed" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a12077-8052-7384-ad05-02190fef7950" xlink:to="loc_srt_MinimumMember_01a12077-8052-7928-83d6-b7bfa2b022ed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a12077-8052-7ea7-882c-2e11b4175bf7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a12077-8052-7384-ad05-02190fef7950" xlink:to="loc_srt_MaximumMember_01a12077-8052-7ea7-882c-2e11b4175bf7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_01a12077-8052-7146-b085-9795abaeed07" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_01a12077-8052-7146-b085-9795abaeed07" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7146-b085-9795abaeed07_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_01a12077-8052-7146-b085-9795abaeed07" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7146-b085-9795abaeed07_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7eea-bde1-57e4c2947826" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_01a12077-8052-7146-b085-9795abaeed07" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7eea-bde1-57e4c2947826" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EclipseBusinessCapitalHoldingsLLCMember_01a12077-8052-7b35-a215-1718092c50c6" xlink:href="bbdc-20260930.xsd#bbdc_EclipseBusinessCapitalHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7eea-bde1-57e4c2947826" xlink:to="loc_bbdc_EclipseBusinessCapitalHoldingsLLCMember_01a12077-8052-7b35-a215-1718092c50c6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_01a12077-8052-7b3e-82ed-775b94ae2b9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_01a12077-8052-7b3e-82ed-775b94ae2b9d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue_01a12077-8052-7fc1-9050-037bd29d3b30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-78a0-8456-ce4a40830c6e" xlink:to="loc_us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue_01a12077-8052-7fc1-9050-037bd29d3b30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_01a12077-8052-747f-9f50-22a4dcc61eae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-78a0-8456-ce4a40830c6e" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_01a12077-8052-747f-9f50-22a4dcc61eae" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSEclipseBusinessCapitalHoldingsLLCDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSEclipseBusinessCapitalHoldingsLLCDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSEclipseBusinessCapitalHoldingsLLCDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-78a0-8456-ce4a40830c6e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-78a0-8456-ce4a40830c6e" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a12077-8052-794b-b3de-14956117e4c8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:to="loc_srt_RangeAxis_01a12077-8052-794b-b3de-14956117e4c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a12077-8052-794b-b3de-14956117e4c8_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a12077-8052-794b-b3de-14956117e4c8" xlink:to="loc_srt_RangeMember_01a12077-8052-794b-b3de-14956117e4c8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a12077-8052-7384-ad05-02190fef7950" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a12077-8052-794b-b3de-14956117e4c8" xlink:to="loc_srt_RangeMember_01a12077-8052-7384-ad05-02190fef7950" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a12077-8052-7928-83d6-b7bfa2b022ed" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a12077-8052-7384-ad05-02190fef7950" xlink:to="loc_srt_MinimumMember_01a12077-8052-7928-83d6-b7bfa2b022ed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a12077-8052-7ea7-882c-2e11b4175bf7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a12077-8052-7384-ad05-02190fef7950" xlink:to="loc_srt_MaximumMember_01a12077-8052-7ea7-882c-2e11b4175bf7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_01a12077-8052-7146-b085-9795abaeed07" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-79a3-a055-93b38e58ed81" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_01a12077-8052-7146-b085-9795abaeed07" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7146-b085-9795abaeed07_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_01a12077-8052-7146-b085-9795abaeed07" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7146-b085-9795abaeed07_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7eea-bde1-57e4c2947826" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryAxis_01a12077-8052-7146-b085-9795abaeed07" xlink:to="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7eea-bde1-57e4c2947826" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EclipseBusinessCapitalHoldingsLLCMember_01a12077-8052-7b35-a215-1718092c50c6" xlink:href="bbdc-20260930.xsd#bbdc_EclipseBusinessCapitalHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentCompanyNonconsolidatedSubsidiaryDomain_01a12077-8052-7eea-bde1-57e4c2947826" xlink:to="loc_bbdc_EclipseBusinessCapitalHoldingsLLCMember_01a12077-8052-7b35-a215-1718092c50c6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue_01a12077-8052-7fc1-9050-037bd29d3b30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-78a0-8456-ce4a40830c6e" xlink:to="loc_us-gaap_InvestmentOwnedUnderlyingFaceAmountAtMarketValue_01a12077-8052-7fc1-9050-037bd29d3b30" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_01a12077-8052-747f-9f50-22a4dcc61eae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-78a0-8456-ce4a40830c6e" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_01a12077-8052-747f-9f50-22a4dcc61eae" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSRocadeHoldingsLLCDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSRocadeHoldingsLLCDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSRocadeHoldingsLLCDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7045-8c7b-753d3d8b5193" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7045-8c7b-753d3d8b5193" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a12074-9e1d-7d11-888a-582c0922af56" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:to="loc_srt_RangeAxis_01a12074-9e1d-7d11-888a-582c0922af56" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a12074-9e1d-7d11-888a-582c0922af56_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a12074-9e1d-7d11-888a-582c0922af56" xlink:to="loc_srt_RangeMember_01a12074-9e1d-7d11-888a-582c0922af56_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a12074-9e1d-79c7-a96a-4927d4d73a00" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a12074-9e1d-7d11-888a-582c0922af56" xlink:to="loc_srt_RangeMember_01a12074-9e1d-79c7-a96a-4927d4d73a00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a12074-9e1d-7631-82cb-61359329454c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a12074-9e1d-79c7-a96a-4927d4d73a00" xlink:to="loc_srt_MinimumMember_01a12074-9e1d-7631-82cb-61359329454c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a12074-9e1d-7bcf-9ff4-bba45b0d2bf0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a12074-9e1d-79c7-a96a-4927d4d73a00" xlink:to="loc_srt_MaximumMember_01a12074-9e1d-7bcf-9ff4-bba45b0d2bf0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a12074-9e1d-7316-87f3-70881ec4f1a6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a12074-9e1d-7316-87f3-70881ec4f1a6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7316-87f3-70881ec4f1a6_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a12074-9e1d-7316-87f3-70881ec4f1a6" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7316-87f3-70881ec4f1a6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7134-8b61-2a4cf593a552" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a12074-9e1d-7316-87f3-70881ec4f1a6" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7134-8b61-2a4cf593a552" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RocadeHoldingsLLCMember_01a12074-9e1d-71ba-bb3d-b487539644c2" xlink:href="bbdc-20260930.xsd#bbdc_RocadeHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7134-8b61-2a4cf593a552" xlink:to="loc_bbdc_RocadeHoldingsLLCMember_01a12074-9e1d-71ba-bb3d-b487539644c2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_01a12074-9e1d-7042-8a31-24cc86aea86a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_01a12074-9e1d-7042-8a31-24cc86aea86a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRatePaidInKind_01a12074-9e1d-7235-b5fc-afccfd8df020" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRatePaidInKind"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7045-8c7b-753d3d8b5193" xlink:to="loc_us-gaap_InvestmentInterestRatePaidInKind_01a12074-9e1d-7235-b5fc-afccfd8df020" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_01a12074-9e1d-7534-b57c-38359cc0df6c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7045-8c7b-753d3d8b5193" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_01a12074-9e1d-7534-b57c-38359cc0df6c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSRocadeHoldingsLLCDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSRocadeHoldingsLLCDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSRocadeHoldingsLLCDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7045-8c7b-753d3d8b5193" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7045-8c7b-753d3d8b5193" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a12074-9e1d-7d11-888a-582c0922af56" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:to="loc_srt_RangeAxis_01a12074-9e1d-7d11-888a-582c0922af56" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a12074-9e1d-7d11-888a-582c0922af56_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_01a12074-9e1d-7d11-888a-582c0922af56" xlink:to="loc_srt_RangeMember_01a12074-9e1d-7d11-888a-582c0922af56_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a12074-9e1d-79c7-a96a-4927d4d73a00" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_01a12074-9e1d-7d11-888a-582c0922af56" xlink:to="loc_srt_RangeMember_01a12074-9e1d-79c7-a96a-4927d4d73a00" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a12074-9e1d-7631-82cb-61359329454c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a12074-9e1d-79c7-a96a-4927d4d73a00" xlink:to="loc_srt_MinimumMember_01a12074-9e1d-7631-82cb-61359329454c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a12074-9e1d-7bcf-9ff4-bba45b0d2bf0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_01a12074-9e1d-79c7-a96a-4927d4d73a00" xlink:to="loc_srt_MaximumMember_01a12074-9e1d-7bcf-9ff4-bba45b0d2bf0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a12074-9e1d-7316-87f3-70881ec4f1a6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-70ba-95e5-76f54490253b" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a12074-9e1d-7316-87f3-70881ec4f1a6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7316-87f3-70881ec4f1a6_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a12074-9e1d-7316-87f3-70881ec4f1a6" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7316-87f3-70881ec4f1a6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7134-8b61-2a4cf593a552" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a12074-9e1d-7316-87f3-70881ec4f1a6" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7134-8b61-2a4cf593a552" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RocadeHoldingsLLCMember_01a12074-9e1d-71ba-bb3d-b487539644c2" xlink:href="bbdc-20260930.xsd#bbdc_RocadeHoldingsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a12074-9e1d-7134-8b61-2a4cf593a552" xlink:to="loc_bbdc_RocadeHoldingsLLCMember_01a12074-9e1d-71ba-bb3d-b487539644c2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInterestRatePaidInKind_01a12074-9e1d-7235-b5fc-afccfd8df020" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInterestRatePaidInKind"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7045-8c7b-753d3d8b5193" xlink:to="loc_us-gaap_InvestmentInterestRatePaidInKind_01a12074-9e1d-7235-b5fc-afccfd8df020" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_01a12074-9e1d-7534-b57c-38359cc0df6c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7045-8c7b-753d3d8b5193" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_01a12074-9e1d-7534-b57c-38359cc0df6c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofFairValueMeasurementInputsandValuationTechniquesDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofFairValueMeasurementInputsandValuationTechniquesDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofFairValueMeasurementInputsandValuationTechniquesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019ffbb6-a0bc-7e2f-8318-aeeb994e20fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019ffbb6-a0bc-7a90-8709-545bc7cab218" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019ffbb6-a0bc-7e2f-8318-aeeb994e20fa" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019ffbb6-a0bc-7a90-8709-545bc7cab218" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-7286-90d1-0794117d7bce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019ffbb6-a0bc-7a90-8709-545bc7cab218" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-7286-90d1-0794117d7bce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7286-90d1-0794117d7bce_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-7286-90d1-0794117d7bce" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7286-90d1-0794117d7bce_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7937-aab7-29832a181d66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-7286-90d1-0794117d7bce" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7937-aab7-29832a181d66" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019ffbb6-a0bc-7936-ad1b-f3ae5505d6d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7937-aab7-29832a181d66" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019ffbb6-a0bc-7936-ad1b-f3ae5505d6d3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7f18-b0b9-3aecf0abda0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019ffbb6-a0bc-7a90-8709-545bc7cab218" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7f18-b0b9-3aecf0abda0a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7f18-b0b9-3aecf0abda0a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7f18-b0b9-3aecf0abda0a" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7f18-b0b9-3aecf0abda0a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-790d-b5d6-ece652621373" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7f18-b0b9-3aecf0abda0a" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-790d-b5d6-ece652621373" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7b4c-9560-aa563ea848ff" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-790d-b5d6-ece652621373" xlink:to="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7b4c-9560-aa563ea848ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-74be-87fb-99ea87437e43" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-790d-b5d6-ece652621373" xlink:to="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-74be-87fb-99ea87437e43" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_StructuredProductsMember_019ffbb6-a0bc-711e-8833-b91a50cb5d97" xlink:href="bbdc-20260930.xsd#bbdc_StructuredProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-790d-b5d6-ece652621373" xlink:to="loc_bbdc_StructuredProductsMember_019ffbb6-a0bc-711e-8833-b91a50cb5d97" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-77d6-af96-f50863ddf8a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-790d-b5d6-ece652621373" xlink:to="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-77d6-af96-f50863ddf8a5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EquityWarrantsMember_019ffbb6-a0bc-7b73-95dd-35f1e3197d4b" xlink:href="bbdc-20260930.xsd#bbdc_EquityWarrantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-790d-b5d6-ece652621373" xlink:to="loc_bbdc_EquityWarrantsMember_019ffbb6-a0bc-7b73-95dd-35f1e3197d4b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RoyaltyRightsMember_019ffbb6-a0bc-7a7d-992e-4a21702055a0" xlink:href="bbdc-20260930.xsd#bbdc_RoyaltyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-790d-b5d6-ece652621373" xlink:to="loc_bbdc_RoyaltyRightsMember_019ffbb6-a0bc-7a7d-992e-4a21702055a0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_019ffbb6-a0bc-7654-a287-1931442c0e55" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019ffbb6-a0bc-7a90-8709-545bc7cab218" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_019ffbb6-a0bc-7654-a287-1931442c0e55" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7654-a287-1931442c0e55_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019ffbb6-a0bc-7654-a287-1931442c0e55" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7654-a287-1931442c0e55_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019ffbb6-a0bc-7654-a287-1931442c0e55" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputMarketYieldMember_019ffbb6-a0bc-7f2f-83cb-dec7e9ebaedb" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputMarketYieldMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_bbdc_MeasurementInputMarketYieldMember_019ffbb6-a0bc-7f2f-83cb-dec7e9ebaedb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputEbitdaMultipleMember_019ffbb6-a0bc-75ab-afb4-13e44780d1f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputEbitdaMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_us-gaap_MeasurementInputEbitdaMultipleMember_019ffbb6-a0bc-75ab-afb4-13e44780d1f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputTangibleBookValueMultipleMember_01a13d7c-a873-79d8-8201-b8a3924b3d5f" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputTangibleBookValueMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_bbdc_MeasurementInputTangibleBookValueMultipleMember_01a13d7c-a873-79d8-8201-b8a3924b3d5f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputExpectedRecoveryMember_019ffbb6-a0bc-7ca7-a1b2-d21e944152b9" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputExpectedRecoveryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_bbdc_MeasurementInputExpectedRecoveryMember_019ffbb6-a0bc-7ca7-a1b2-d21e944152b9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputTransactionPriceMember_019ffbb6-a0bc-71af-86a1-f4d450915080" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputTransactionPriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_bbdc_MeasurementInputTransactionPriceMember_019ffbb6-a0bc-71af-86a1-f4d450915080" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputRevenueMultipleMember_019ffbb6-a0bc-7c2d-b9a8-4ada7ddc89f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputRevenueMultipleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_us-gaap_MeasurementInputRevenueMultipleMember_019ffbb6-a0bc-7c2d-b9a8-4ada7ddc89f7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputPriceVolatilityMember_019ffbb6-a0bc-7285-bfcf-9b18bf062f0b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputPriceVolatilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_us-gaap_MeasurementInputPriceVolatilityMember_019ffbb6-a0bc-7285-bfcf-9b18bf062f0b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputDiscountRateMember_019ffbb6-a0bc-75ee-97ce-8a2a7136e63b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputDiscountRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_us-gaap_MeasurementInputDiscountRateMember_019ffbb6-a0bc-75ee-97ce-8a2a7136e63b" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputLiabilityMember_019ffbb6-a0bc-726f-aa48-5c5fe73f28b0" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputLiabilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7cb7-9c87-60f0a541a177" xlink:to="loc_bbdc_MeasurementInputLiabilityMember_019ffbb6-a0bc-726f-aa48-5c5fe73f28b0" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-72c5-840e-d82ac6b290f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019ffbb6-a0bc-7a90-8709-545bc7cab218" xlink:to="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-72c5-840e-d82ac6b290f4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-72c5-840e-d82ac6b290f4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-72c5-840e-d82ac6b290f4" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-72c5-840e-d82ac6b290f4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-72c5-840e-d82ac6b290f4" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationYieldAnalysisMember_019ffbb6-a0bc-75cd-9941-fd87c9be3417" xlink:href="bbdc-20260930.xsd#bbdc_ValuationYieldAnalysisMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:to="loc_bbdc_ValuationYieldAnalysisMember_019ffbb6-a0bc-75cd-9941-fd87c9be3417" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketApproachValuationTechniqueMember_019ffbb6-a0bc-7c7c-ac13-7d1ed3284c0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MarketApproachValuationTechniqueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:to="loc_us-gaap_MarketApproachValuationTechniqueMember_019ffbb6-a0bc-7c7c-ac13-7d1ed3284c0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationTechniqueExpectedRecoveryMember_019ffbb6-a0bc-702d-9e47-513d275e486f" xlink:href="bbdc-20260930.xsd#bbdc_ValuationTechniqueExpectedRecoveryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:to="loc_bbdc_ValuationTechniqueExpectedRecoveryMember_019ffbb6-a0bc-702d-9e47-513d275e486f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationRecentTransactionMember_019ffbb6-a0bc-77e3-892a-59173d830040" xlink:href="bbdc-20260930.xsd#bbdc_ValuationRecentTransactionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:to="loc_bbdc_ValuationRecentTransactionMember_019ffbb6-a0bc-77e3-892a-59173d830040" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BlackScholesMertonModelMember_019ffbb6-a0bc-75ef-8638-135ee8dd4461" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BlackScholesMertonModelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:to="loc_us-gaap_BlackScholesMertonModelMember_019ffbb6-a0bc-75ef-8638-135ee8dd4461" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDiscountedCashFlowMember_019ffbb6-a0bc-71ea-8b42-4152a1e554ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDiscountedCashFlowMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:to="loc_us-gaap_ValuationTechniqueDiscountedCashFlowMember_019ffbb6-a0bc-71ea-8b42-4152a1e554ad" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationTechniqueNetAssetApproachMember_019ffbb6-a0bc-7410-983d-2d6c78c5884c" xlink:href="bbdc-20260930.xsd#bbdc_ValuationTechniqueNetAssetApproachMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:to="loc_bbdc_ValuationTechniqueNetAssetApproachMember_019ffbb6-a0bc-7410-983d-2d6c78c5884c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationUnadjustedPricesFromIndependentPricingServicesAndIndependentIndicativeBrokerQuotesMember_019ffbb6-a0bc-7a9b-ba4f-a7b8e07473b1" xlink:href="bbdc-20260930.xsd#bbdc_ValuationUnadjustedPricesFromIndependentPricingServicesAndIndependentIndicativeBrokerQuotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7daa-b292-e901ac861cf0" xlink:to="loc_bbdc_ValuationUnadjustedPricesFromIndependentPricingServicesAndIndependentIndicativeBrokerQuotesMember_019ffbb6-a0bc-7a9b-ba4f-a7b8e07473b1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019ffbb6-a0bc-7178-a698-bcc8ebe2c066" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019ffbb6-a0bc-7a90-8709-545bc7cab218" xlink:to="loc_srt_RangeAxis_019ffbb6-a0bc-7178-a698-bcc8ebe2c066" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ffbb6-a0bc-7178-a698-bcc8ebe2c066_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019ffbb6-a0bc-7178-a698-bcc8ebe2c066" xlink:to="loc_srt_RangeMember_019ffbb6-a0bc-7178-a698-bcc8ebe2c066_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ffbb6-a0bc-7fcb-b7dd-c1ccfd6cbc81" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019ffbb6-a0bc-7178-a698-bcc8ebe2c066" xlink:to="loc_srt_RangeMember_019ffbb6-a0bc-7fcb-b7dd-c1ccfd6cbc81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019ffbb6-a0bc-74bc-a1bd-bdba5c761d80" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ffbb6-a0bc-7fcb-b7dd-c1ccfd6cbc81" xlink:to="loc_srt_MinimumMember_019ffbb6-a0bc-74bc-a1bd-bdba5c761d80" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019ffbb6-a0bc-7677-9447-46a8de770ea8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ffbb6-a0bc-7fcb-b7dd-c1ccfd6cbc81" xlink:to="loc_srt_MaximumMember_019ffbb6-a0bc-7677-9447-46a8de770ea8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_WeightedAverageMember_019ffbb6-a0bc-70b7-bef2-4ff97b050df2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_WeightedAverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ffbb6-a0bc-7fcb-b7dd-c1ccfd6cbc81" xlink:to="loc_srt_WeightedAverageMember_019ffbb6-a0bc-70b7-bef2-4ff97b050df2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-796b-a8cb-1f49727cfbff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019ffbb6-a0bc-7e2f-8318-aeeb994e20fa" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-796b-a8cb-1f49727cfbff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyInvestmentOwnedFairValueMeasurementInput_019ffbb6-a0bc-7fa6-99bb-87f6455f5f18" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyInvestmentOwnedFairValueMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019ffbb6-a0bc-7e2f-8318-aeeb994e20fa" xlink:to="loc_us-gaap_InvestmentCompanyInvestmentOwnedFairValueMeasurementInput_019ffbb6-a0bc-7fa6-99bb-87f6455f5f18" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSValuationInputsDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSValuationInputsDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSValuationInputsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7537-ae95-4031325d3ebc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7df6-9400-a8355d4d1bfd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7537-ae95-4031325d3ebc" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7df6-9400-a8355d4d1bfd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PreviousValuationAndTechniqueAxis_019ffbb6-a0bc-763f-afb7-3b95e10d20d0" xlink:href="bbdc-20260930.xsd#bbdc_PreviousValuationAndTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7df6-9400-a8355d4d1bfd" xlink:to="loc_bbdc_PreviousValuationAndTechniqueAxis_019ffbb6-a0bc-763f-afb7-3b95e10d20d0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PreviousValuationAndTechniqueDomain_019ffbb6-a0bc-763f-afb7-3b95e10d20d0_default" xlink:href="bbdc-20260930.xsd#bbdc_PreviousValuationAndTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_bbdc_PreviousValuationAndTechniqueAxis_019ffbb6-a0bc-763f-afb7-3b95e10d20d0" xlink:to="loc_bbdc_PreviousValuationAndTechniqueDomain_019ffbb6-a0bc-763f-afb7-3b95e10d20d0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PreviousValuationAndTechniqueDomain_019ffbb6-a0bc-7ad8-9bdd-10c0dbdfc303" xlink:href="bbdc-20260930.xsd#bbdc_PreviousValuationAndTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_bbdc_PreviousValuationAndTechniqueAxis_019ffbb6-a0bc-763f-afb7-3b95e10d20d0" xlink:to="loc_bbdc_PreviousValuationAndTechniqueDomain_019ffbb6-a0bc-7ad8-9bdd-10c0dbdfc303" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationYieldAnalysisMember_019ffbb6-a0bc-7ec6-ada6-49ab8df9f40a" xlink:href="bbdc-20260930.xsd#bbdc_ValuationYieldAnalysisMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_PreviousValuationAndTechniqueDomain_019ffbb6-a0bc-7ad8-9bdd-10c0dbdfc303" xlink:to="loc_bbdc_ValuationYieldAnalysisMember_019ffbb6-a0bc-7ec6-ada6-49ab8df9f40a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketApproachValuationTechniqueMember_019ffbb6-a0bc-7eba-a458-eaa27bc21e73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MarketApproachValuationTechniqueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_PreviousValuationAndTechniqueDomain_019ffbb6-a0bc-7ad8-9bdd-10c0dbdfc303" xlink:to="loc_us-gaap_MarketApproachValuationTechniqueMember_019ffbb6-a0bc-7eba-a458-eaa27bc21e73" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NetAssetApproachMember_019ffbb6-a0bc-7e49-8c9b-4b7e2598c089" xlink:href="bbdc-20260930.xsd#bbdc_NetAssetApproachMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_PreviousValuationAndTechniqueDomain_019ffbb6-a0bc-7ad8-9bdd-10c0dbdfc303" xlink:to="loc_bbdc_NetAssetApproachMember_019ffbb6-a0bc-7e49-8c9b-4b7e2598c089" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationUnadjustedPricesFromIndependentPricingServicesAndIndependentIndicativeBrokerQuotesMember_019ffbb6-a0bc-7187-883b-8a7603b7bfc5" xlink:href="bbdc-20260930.xsd#bbdc_ValuationUnadjustedPricesFromIndependentPricingServicesAndIndependentIndicativeBrokerQuotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_PreviousValuationAndTechniqueDomain_019ffbb6-a0bc-7ad8-9bdd-10c0dbdfc303" xlink:to="loc_bbdc_ValuationUnadjustedPricesFromIndependentPricingServicesAndIndependentIndicativeBrokerQuotesMember_019ffbb6-a0bc-7187-883b-8a7603b7bfc5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-70f0-a564-edad17c8100b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7df6-9400-a8355d4d1bfd" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-70f0-a564-edad17c8100b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-70f0-a564-edad17c8100b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-70f0-a564-edad17c8100b" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-70f0-a564-edad17c8100b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-70f0-a564-edad17c8100b" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7786-8956-c70d17c0741a" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:to="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7786-8956-c70d17c0741a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-76ee-b981-b4f94bda1492" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:to="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-76ee-b981-b4f94bda1492" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-7bb7-b0c5-2a25986dd233" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:to="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-7bb7-b0c5-2a25986dd233" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesStructuredProductPositionMember_019ffbb6-a0bc-72f3-9875-e6bc4dcefb92" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesStructuredProductPositionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:to="loc_bbdc_DebtSecuritiesStructuredProductPositionMember_019ffbb6-a0bc-72f3-9875-e6bc4dcefb92" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentsWithNoPreviousContractualCommitmentToProvideFinancingMember_019ffbb6-a0bc-7ad6-93d2-9a2d56484dd5" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentsWithNoPreviousContractualCommitmentToProvideFinancingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:to="loc_bbdc_InvestmentsWithNoPreviousContractualCommitmentToProvideFinancingMember_019ffbb6-a0bc-7ad6-93d2-9a2d56484dd5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentWithPreviousCommitmentToProvideFinancingMember_019ffbb6-a0bc-7907-beac-ef93a2d47ae9" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentWithPreviousCommitmentToProvideFinancingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:to="loc_bbdc_InvestmentWithPreviousCommitmentToProvideFinancingMember_019ffbb6-a0bc-7907-beac-ef93a2d47ae9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember_019ffbb6-a0bc-7aff-b680-7b127633edfe" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7d17-8b02-a503c593b043" xlink:to="loc_bbdc_InvestmentExcludingShortTermInvestmentWithPreviousCommitmentToProvideFinancingMember_019ffbb6-a0bc-7aff-b680-7b127633edfe" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-7538-98b7-c79553b5a95a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7df6-9400-a8355d4d1bfd" xlink:to="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-7538-98b7-c79553b5a95a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7538-98b7-c79553b5a95a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-7538-98b7-c79553b5a95a" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7538-98b7-c79553b5a95a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-780a-abf0-797ebe207912" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-7538-98b7-c79553b5a95a" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-780a-abf0-797ebe207912" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketApproachValuationTechniqueMember_019ffbb6-a0bc-7fb2-9ae8-4cb22d115fd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MarketApproachValuationTechniqueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-780a-abf0-797ebe207912" xlink:to="loc_us-gaap_MarketApproachValuationTechniqueMember_019ffbb6-a0bc-7fb2-9ae8-4cb22d115fd4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationYieldAnalysisMember_019ffbb6-a0bc-7f05-b3e8-beee0f90537b" xlink:href="bbdc-20260930.xsd#bbdc_ValuationYieldAnalysisMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-780a-abf0-797ebe207912" xlink:to="loc_bbdc_ValuationYieldAnalysisMember_019ffbb6-a0bc-7f05-b3e8-beee0f90537b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BlackScholesMertonModelMember_019ffbb6-a0bc-7344-a48d-0842b7d108d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BlackScholesMertonModelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-780a-abf0-797ebe207912" xlink:to="loc_us-gaap_BlackScholesMertonModelMember_019ffbb6-a0bc-7344-a48d-0842b7d108d6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationTechniqueExpectedRecoveryMember_019ffbb6-a0bc-7e97-b290-e52a001ab8c0" xlink:href="bbdc-20260930.xsd#bbdc_ValuationTechniqueExpectedRecoveryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-780a-abf0-797ebe207912" xlink:to="loc_bbdc_ValuationTechniqueExpectedRecoveryMember_019ffbb6-a0bc-7e97-b290-e52a001ab8c0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedNumberOfInvestments_019ffbb6-a0bc-754b-90a2-99fcfcfee67e" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedNumberOfInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7537-ae95-4031325d3ebc" xlink:to="loc_bbdc_InvestmentOwnedNumberOfInvestments_019ffbb6-a0bc-754b-90a2-99fcfcfee67e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-70bc-a25e-10af81f5f633" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7537-ae95-4031325d3ebc" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-70bc-a25e-10af81f5f633" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetRecurringBasisStillHeldUnrealizedGainLossStatementOfIncomeExtensibleList_019ffbb6-a0bc-7cdc-b681-043ec3e5ed52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetRecurringBasisStillHeldUnrealizedGainLossStatementOfIncomeExtensibleList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7537-ae95-4031325d3ebc" xlink:to="loc_us-gaap_FairValueAssetRecurringBasisStillHeldUnrealizedGainLossStatementOfIncomeExtensibleList_019ffbb6-a0bc-7cdc-b681-043ec3e5ed52" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_019ffbb6-a0bc-729a-b7fd-96c75f36fe6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7537-ae95-4031325d3ebc" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss_019ffbb6-a0bc-729a-b7fd-96c75f36fe6a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_019ffbb6-a0bc-746e-851f-f77b9385fc13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7537-ae95-4031325d3ebc" xlink:to="loc_us-gaap_PaymentsForPurchaseOfInvestmentOperatingActivity_019ffbb6-a0bc-746e-851f-f77b9385fc13" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-72d3-9242-f9a7f85e7ae8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7d3f-aa90-1e9e8a5217ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-72d3-9242-f9a7f85e7ae8" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7d3f-aa90-1e9e8a5217ac" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-7228-9d4e-e0b4c8d5fc30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7d3f-aa90-1e9e8a5217ac" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-7228-9d4e-e0b4c8d5fc30" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7228-9d4e-e0b4c8d5fc30_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-7228-9d4e-e0b4c8d5fc30" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7228-9d4e-e0b4c8d5fc30_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-70ba-8617-93925a9cbf47" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-7228-9d4e-e0b4c8d5fc30" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-70ba-8617-93925a9cbf47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019ffbb6-a0bc-780d-8ac9-2f1e612d22b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-70ba-8617-93925a9cbf47" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019ffbb6-a0bc-780d-8ac9-2f1e612d22b0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019ffbb6-a0bc-7d0b-8023-489a60def86a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-70ba-8617-93925a9cbf47" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019ffbb6-a0bc-7d0b-8023-489a60def86a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019ffbb6-a0bc-7a0a-8c69-b4b6a8f486be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-70ba-8617-93925a9cbf47" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019ffbb6-a0bc-7a0a-8c69-b4b6a8f486be" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7585-a4b1-3b46097cc403" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7d3f-aa90-1e9e8a5217ac" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7585-a4b1-3b46097cc403" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7585-a4b1-3b46097cc403_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7585-a4b1-3b46097cc403" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7585-a4b1-3b46097cc403_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7585-a4b1-3b46097cc403" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7dd3-8d70-e5ad7372749a" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:to="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7dd3-8d70-e5ad7372749a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-7f16-b640-f7b254bfe2d9" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:to="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-7f16-b640-f7b254bfe2d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_StructuredProductsMember_019ffbb6-a0bc-76b1-8fb4-7d2077ce9911" xlink:href="bbdc-20260930.xsd#bbdc_StructuredProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:to="loc_bbdc_StructuredProductsMember_019ffbb6-a0bc-76b1-8fb4-7d2077ce9911" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-7ab0-9a7b-0b3cb5def24b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:to="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-7ab0-9a7b-0b3cb5def24b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EquityWarrantsMember_019ffbb6-a0bc-7af3-929d-bb84dbf1f0f5" xlink:href="bbdc-20260930.xsd#bbdc_EquityWarrantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:to="loc_bbdc_EquityWarrantsMember_019ffbb6-a0bc-7af3-929d-bb84dbf1f0f5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RoyaltyRightsMember_019ffbb6-a0bc-79d1-9ffb-d4a57a3b9a81" xlink:href="bbdc-20260930.xsd#bbdc_RoyaltyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:to="loc_bbdc_RoyaltyRightsMember_019ffbb6-a0bc-79d1-9ffb-d4a57a3b9a81" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentsSubjectToLevelingMember_019ffbb6-a0bc-73a4-96ab-be67d40bec57" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentsSubjectToLevelingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:to="loc_bbdc_InvestmentsSubjectToLevelingMember_019ffbb6-a0bc-73a4-96ab-be67d40bec57" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentInJointVenturesMember_019ffbb6-a0bc-771a-aac0-3fb5935ed0d1" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentInJointVenturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7446-9925-73b1ffbfe2c2" xlink:to="loc_bbdc_InvestmentInJointVenturesMember_019ffbb6-a0bc-771a-aac0-3fb5935ed0d1" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-76d2-bff6-4581a6e9e6aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-72d3-9242-f9a7f85e7ae8" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019ffbb6-a0bc-76d2-bff6-4581a6e9e6aa" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisUnobservableInputReconciliationDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisUnobservableInputReconciliationDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisUnobservableInputReconciliationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-748b-941a-25433c51fa58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7fce-8a9f-9c0919522c95" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-748b-941a-25433c51fa58" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7fce-8a9f-9c0919522c95" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7210-8c76-440df3c2e9fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7fce-8a9f-9c0919522c95" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7210-8c76-440df3c2e9fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7210-8c76-440df3c2e9fd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7210-8c76-440df3c2e9fd" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7210-8c76-440df3c2e9fd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7210-8c76-440df3c2e9fd" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7de1-beee-7919ccd60678" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7de1-beee-7919ccd60678" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-76ec-a78f-8e250ff0755d" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-76ec-a78f-8e250ff0755d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_StructuredProductsMember_019ffbb6-a0bc-7c07-8c8f-2f128a2dfd8c" xlink:href="bbdc-20260930.xsd#bbdc_StructuredProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_StructuredProductsMember_019ffbb6-a0bc-7c07-8c8f-2f128a2dfd8c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-703a-9aa8-4521ac584f9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-703a-9aa8-4521ac584f9d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EquityWarrantsMember_019ffbb6-a0bc-75aa-8607-100915075efa" xlink:href="bbdc-20260930.xsd#bbdc_EquityWarrantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_EquityWarrantsMember_019ffbb6-a0bc-75aa-8607-100915075efa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RoyaltyRightsMember_019ffbb6-a0bc-78ff-8656-a32973672b99" xlink:href="bbdc-20260930.xsd#bbdc_RoyaltyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_RoyaltyRightsMember_019ffbb6-a0bc-78ff-8656-a32973672b99" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ffbb6-a0bc-75fe-847e-b83965650c5b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7fce-8a9f-9c0919522c95" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019ffbb6-a0bc-75fe-847e-b83965650c5b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-748b-941a-25433c51fa58" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019ffbb6-a0bc-72cc-ae63-c5d7b9e80fdb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019ffbb6-a0bc-72cc-ae63-c5d7b9e80fdb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_019ffbb6-a0bc-7a6c-a146-45ca2372dd35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_019ffbb6-a0bc-7a6c-a146-45ca2372dd35" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetRestructuring_019ffbb6-a0bc-7bb0-88fa-c9a2cd91b7b5" xlink:href="bbdc-20260930.xsd#bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetRestructuring"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetRestructuring_019ffbb6-a0bc-7bb0-88fa-c9a2cd91b7b5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_019ffbb6-a0bc-75a0-a360-1b92fb1332c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_019ffbb6-a0bc-75a0-a360-1b92fb1332c6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_019ffbb6-a0bc-71f3-bffa-ccc732495da5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_019ffbb6-a0bc-71f3-bffa-ccc732495da5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_019ffbb6-a0bc-7eb6-9318-cf7d854e974b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_019ffbb6-a0bc-7eb6-9318-cf7d854e974b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLoanOriginationFeesReceived_019ffbb6-a0bc-74ea-a602-374b72bd34e0" xlink:href="bbdc-20260930.xsd#bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLoanOriginationFeesReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLoanOriginationFeesReceived_019ffbb6-a0bc-74ea-a602-374b72bd34e0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPrincipalRepaymentReceived_019ffbb6-a0bc-73e1-bc0e-68ccbb93ace7" xlink:href="bbdc-20260930.xsd#bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPrincipalRepaymentReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPrincipalRepaymentReceived_019ffbb6-a0bc-73e1-bc0e-68ccbb93ace7" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_019ffbb6-a0bc-7bd1-8a3a-9231a920c582" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_019ffbb6-a0bc-7bd1-8a3a-9231a920c582" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019ffbb6-a0bc-783a-8fd1-830b668567e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList_019ffbb6-a0bc-780a-b821-b51f62a50b66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-748b-941a-25433c51fa58" xlink:to="loc_us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList_019ffbb6-a0bc-780a-b821-b51f62a50b66" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisUnobservableInputReconciliationDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisUnobservableInputReconciliationDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSScheduleofFairValueAssetsMeasuredonRecurringBasisUnobservableInputReconciliationDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-748b-941a-25433c51fa58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7fce-8a9f-9c0919522c95" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-748b-941a-25433c51fa58" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7fce-8a9f-9c0919522c95" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7210-8c76-440df3c2e9fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7fce-8a9f-9c0919522c95" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7210-8c76-440df3c2e9fd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7210-8c76-440df3c2e9fd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7210-8c76-440df3c2e9fd" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7210-8c76-440df3c2e9fd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7210-8c76-440df3c2e9fd" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7de1-beee-7919ccd60678" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_DebtSecuritiesSeniorDebtAnd1stLienNotesMember_019ffbb6-a0bc-7de1-beee-7919ccd60678" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-76ec-a78f-8e250ff0755d" xlink:href="bbdc-20260930.xsd#bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_DebtSecuritiesSubordinatedDebtAnd2ndLienNotesMember_019ffbb6-a0bc-76ec-a78f-8e250ff0755d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_StructuredProductsMember_019ffbb6-a0bc-7c07-8c8f-2f128a2dfd8c" xlink:href="bbdc-20260930.xsd#bbdc_StructuredProductsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_StructuredProductsMember_019ffbb6-a0bc-7c07-8c8f-2f128a2dfd8c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-703a-9aa8-4521ac584f9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_us-gaap_EquitySecuritiesMember_019ffbb6-a0bc-703a-9aa8-4521ac584f9d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EquityWarrantsMember_019ffbb6-a0bc-75aa-8607-100915075efa" xlink:href="bbdc-20260930.xsd#bbdc_EquityWarrantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_EquityWarrantsMember_019ffbb6-a0bc-75aa-8607-100915075efa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_RoyaltyRightsMember_019ffbb6-a0bc-78ff-8656-a32973672b99" xlink:href="bbdc-20260930.xsd#bbdc_RoyaltyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7833-ac70-d4e8bede4252" xlink:to="loc_bbdc_RoyaltyRightsMember_019ffbb6-a0bc-78ff-8656-a32973672b99" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-748b-941a-25433c51fa58" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019ffbb6-a0bc-72cc-ae63-c5d7b9e80fdb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019ffbb6-a0bc-72cc-ae63-c5d7b9e80fdb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_019ffbb6-a0bc-7a6c-a146-45ca2372dd35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_019ffbb6-a0bc-7a6c-a146-45ca2372dd35" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetRestructuring_019ffbb6-a0bc-7bb0-88fa-c9a2cd91b7b5" xlink:href="bbdc-20260930.xsd#bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetRestructuring"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetRestructuring_019ffbb6-a0bc-7bb0-88fa-c9a2cd91b7b5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_019ffbb6-a0bc-75a0-a360-1b92fb1332c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet_019ffbb6-a0bc-75a0-a360-1b92fb1332c6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_019ffbb6-a0bc-71f3-bffa-ccc732495da5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_019ffbb6-a0bc-71f3-bffa-ccc732495da5" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_019ffbb6-a0bc-7eb6-9318-cf7d854e974b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_019ffbb6-a0bc-7eb6-9318-cf7d854e974b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLoanOriginationFeesReceived_019ffbb6-a0bc-74ea-a602-374b72bd34e0" xlink:href="bbdc-20260930.xsd#bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLoanOriginationFeesReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetLoanOriginationFeesReceived_019ffbb6-a0bc-74ea-a602-374b72bd34e0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPrincipalRepaymentReceived_019ffbb6-a0bc-73e1-bc0e-68ccbb93ace7" xlink:href="bbdc-20260930.xsd#bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPrincipalRepaymentReceived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_bbdc_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPrincipalRepaymentReceived_019ffbb6-a0bc-73e1-bc0e-68ccbb93ace7" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_019ffbb6-a0bc-7bd1-8a3a-9231a920c582" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019ffbb6-a0bc-70ce-ae68-c63cdce6b954" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_019ffbb6-a0bc-7bd1-8a3a-9231a920c582" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019ffbb6-a0bc-783a-8fd1-830b668567e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList_019ffbb6-a0bc-780a-b821-b51f62a50b66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-748b-941a-25433c51fa58" xlink:to="loc_us-gaap_FairValueRecurringBasisUnobservableInputReconciliationAssetGainLossStatementOfIncomeExtensibleList_019ffbb6-a0bc-780a-b821-b51f62a50b66" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSInvestmentIncomePaymentinKindIncomeandSegmentsDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSInvestmentIncomePaymentinKindIncomeandSegmentsDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSInvestmentIncomePaymentinKindIncomeandSegmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-788a-8763-12cf51ed6240" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7b7a-9a48-1a4f3a10957c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-788a-8763-12cf51ed6240" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7b7a-9a48-1a4f3a10957c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionAxis_019ffbb6-a0bc-73af-85cb-6984d4d5c20d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-7b7a-9a48-1a4f3a10957c" xlink:to="loc_us-gaap_AssetAcquisitionAxis_019ffbb6-a0bc-73af-85cb-6984d4d5c20d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_019ffbb6-a0bc-73af-85cb-6984d4d5c20d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetAcquisitionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AssetAcquisitionAxis_019ffbb6-a0bc-73af-85cb-6984d4d5c20d" xlink:to="loc_us-gaap_AssetAcquisitionDomain_019ffbb6-a0bc-73af-85cb-6984d4d5c20d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_019ffbb6-a0bc-7be5-8e01-113d30275e69" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetAcquisitionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AssetAcquisitionAxis_019ffbb6-a0bc-73af-85cb-6984d4d5c20d" xlink:to="loc_us-gaap_AssetAcquisitionDomain_019ffbb6-a0bc-7be5-8e01-113d30275e69" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SierraMergerMember_019ffbb6-a0bc-764c-8463-997305a336aa" xlink:href="bbdc-20260930.xsd#bbdc_SierraMergerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetAcquisitionDomain_019ffbb6-a0bc-7be5-8e01-113d30275e69" xlink:to="loc_bbdc_SierraMergerMember_019ffbb6-a0bc-764c-8463-997305a336aa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NumberOfNonAccrualPortfolioCompanies_019ffbb6-a0bc-7aa0-86ea-d3376a65582a" xlink:href="bbdc-20260930.xsd#bbdc_NumberOfNonAccrualPortfolioCompanies"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-788a-8763-12cf51ed6240" xlink:to="loc_bbdc_NumberOfNonAccrualPortfolioCompanies_019ffbb6-a0bc-7aa0-86ea-d3376a65582a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NumberOfNonAccrualPortfolioCompaniesOriginatedByTheCompany_019ffbb6-a0bc-770f-8116-7922c6b49e2d" xlink:href="bbdc-20260930.xsd#bbdc_NumberOfNonAccrualPortfolioCompaniesOriginatedByTheCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-788a-8763-12cf51ed6240" xlink:to="loc_bbdc_NumberOfNonAccrualPortfolioCompaniesOriginatedByTheCompany_019ffbb6-a0bc-770f-8116-7922c6b49e2d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NumberOfPaidInKindPartialNonAccrualPortfolioCompaniesOriginatedByTheCompany_019ffbb6-a0bc-734b-aa9d-a1a978fa93f4" xlink:href="bbdc-20260930.xsd#bbdc_NumberOfPaidInKindPartialNonAccrualPortfolioCompaniesOriginatedByTheCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-788a-8763-12cf51ed6240" xlink:to="loc_bbdc_NumberOfPaidInKindPartialNonAccrualPortfolioCompaniesOriginatedByTheCompany_019ffbb6-a0bc-734b-aa9d-a1a978fa93f4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfReportableSegments_019ffbb6-a0bc-7270-8f16-d25a34edd22e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfReportableSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-788a-8763-12cf51ed6240" xlink:to="loc_us-gaap_NumberOfReportableSegments_019ffbb6-a0bc-7270-8f16-d25a34edd22e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfOperatingSegments_019ffbb6-a0bc-7033-b3d1-545bf94fe26f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfOperatingSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-788a-8763-12cf51ed6240" xlink:to="loc_us-gaap_NumberOfOperatingSegments_019ffbb6-a0bc-7033-b3d1-545bf94fe26f" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/INVESTMENTSConcentrationofCreditRiskandInvestmentsDenominatedinForeignCurrenciesDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#INVESTMENTSConcentrationofCreditRiskandInvestmentsDenominatedinForeignCurrenciesDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/INVESTMENTSConcentrationofCreditRiskandInvestmentsDenominatedinForeignCurrenciesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7220-a7a4-4855a88cea24" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-74aa-9c77-995bd7aea14f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7220-a7a4-4855a88cea24" xlink:to="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-74aa-9c77-995bd7aea14f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7a83-b4d3-4892f3ae02a6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-74aa-9c77-995bd7aea14f" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7a83-b4d3-4892f3ae02a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7a83-b4d3-4892f3ae02a6_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7a83-b4d3-4892f3ae02a6" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7a83-b4d3-4892f3ae02a6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7890-b2b1-06e9d924d896" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019ffbb6-a0bc-7a83-b4d3-4892f3ae02a6" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7890-b2b1-06e9d924d896" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SinglePortfolioCompanyMember_019ffbb6-a0bc-7fc6-ad2c-cadfa8f26cdd" xlink:href="bbdc-20260930.xsd#bbdc_SinglePortfolioCompanyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019ffbb6-a0bc-7890-b2b1-06e9d924d896" xlink:to="loc_bbdc_SinglePortfolioCompanyMember_019ffbb6-a0bc-7fc6-ad2c-cadfa8f26cdd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-756b-a5f8-75b87d79373e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-74aa-9c77-995bd7aea14f" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-756b-a5f8-75b87d79373e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-756b-a5f8-75b87d79373e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-756b-a5f8-75b87d79373e" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-756b-a5f8-75b87d79373e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7b5b-a115-9bc8be826376" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019ffbb6-a0bc-756b-a5f8-75b87d79373e" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7b5b-a115-9bc8be826376" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedAtFairValueMember_019ffbb6-a0bc-7c9c-9b19-3d0fd5b40391" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedAtFairValueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019ffbb6-a0bc-7b5b-a115-9bc8be826376" xlink:to="loc_bbdc_InvestmentOwnedAtFairValueMember_019ffbb6-a0bc-7c9c-9b19-3d0fd5b40391" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7b32-b362-722af848d0f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-74aa-9c77-995bd7aea14f" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7b32-b362-722af848d0f9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7b32-b362-722af848d0f9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7b32-b362-722af848d0f9" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7b32-b362-722af848d0f9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7f15-89f6-b2426d9b1a86" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_019ffbb6-a0bc-7b32-b362-722af848d0f9" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7f15-89f6-b2426d9b1a86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PortfolioCompanyInvestmentRiskMember_019ffbb6-a0bc-7c12-9a6c-6eabd3fd49e0" xlink:href="bbdc-20260930.xsd#bbdc_PortfolioCompanyInvestmentRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019ffbb6-a0bc-7f15-89f6-b2426d9b1a86" xlink:to="loc_bbdc_PortfolioCompanyInvestmentRiskMember_019ffbb6-a0bc-7c12-9a6c-6eabd3fd49e0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7268-8342-47f78484246d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentsTable_019ffbb6-a0bc-74aa-9c77-995bd7aea14f" xlink:to="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7268-8342-47f78484246d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7268-8342-47f78484246d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7268-8342-47f78484246d" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7268-8342-47f78484246d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_019ffbb6-a0bc-7268-8342-47f78484246d" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInCanadianDollarsMember_019ffbb6-a0bc-7e96-baa1-92f53793afb8" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInCanadianDollarsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInCanadianDollarsMember_019ffbb6-a0bc-7e96-baa1-92f53793afb8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInDanishKronerMember_019ffbb6-a0bc-7708-ab59-23306e71bb0a" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInDanishKronerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInDanishKronerMember_019ffbb6-a0bc-7708-ab59-23306e71bb0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInAustralianDollarsMember_019ffbb6-a0bc-79de-9f37-9c936c771e5a" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInAustralianDollarsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInAustralianDollarsMember_019ffbb6-a0bc-79de-9f37-9c936c771e5a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInNewZealandDollarsMember_019ffbb6-a0bc-7d8b-aa49-b12381bc1100" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInNewZealandDollarsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInNewZealandDollarsMember_019ffbb6-a0bc-7d8b-aa49-b12381bc1100" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInNorwegianKroneMember_019ffbb6-a0bc-7cd6-b0d0-e81c3d2bf532" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInNorwegianKroneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInNorwegianKroneMember_019ffbb6-a0bc-7cd6-b0d0-e81c3d2bf532" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInSwissFrancsMember_019ffbb6-a0bc-74c4-b813-b2a756683ce6" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInSwissFrancsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInSwissFrancsMember_019ffbb6-a0bc-74c4-b813-b2a756683ce6" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInSwedishKroneMember_019ffbb6-a0bc-72d6-a9c4-8fb8a1a6bb17" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInSwedishKroneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInSwedishKroneMember_019ffbb6-a0bc-72d6-a9c4-8fb8a1a6bb17" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInEurosMember_019ffbb6-a0bc-7459-b100-cd913dbe77a5" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInEurosMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInEurosMember_019ffbb6-a0bc-7459-b100-cd913dbe77a5" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentDenominatedInBritishPoundsSterlingMember_019ffbb6-a0bc-72f5-8f5b-25fa36631ffe" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentDenominatedInBritishPoundsSterlingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_019ffbb6-a0bc-7450-a00d-216c8647541a" xlink:to="loc_bbdc_InvestmentDenominatedInBritishPoundsSterlingMember_019ffbb6-a0bc-72f5-8f5b-25fa36631ffe" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019ffbb6-a0bc-7633-865f-77e596bb40e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7220-a7a4-4855a88cea24" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019ffbb6-a0bc-7633-865f-77e596bb40e5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InvestmentOwnedNumberOfInvestments_019ffbb6-a0bc-7ada-9c71-9949928a546a" xlink:href="bbdc-20260930.xsd#bbdc_InvestmentOwnedNumberOfInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentsLineItems_019ffbb6-a0bc-7220-a7a4-4855a88cea24" xlink:to="loc_bbdc_InvestmentOwnedNumberOfInvestments_019ffbb6-a0bc-7ada-9c71-9949928a546a" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/BORROWINGSScheduleofBorrowingsOutstandingDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#BORROWINGSScheduleofBorrowingsOutstandingDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/BORROWINGSScheduleofBorrowingsOutstandingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-76a8-b09a-4b861ced79b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-78b1-bd8f-45afb8e180a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-76a8-b09a-4b861ced79b8" xlink:to="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-78b1-bd8f-45afb8e180a6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-78bb-a2ac-9232510219cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-78b1-bd8f-45afb8e180a6" xlink:to="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-78bb-a2ac-9232510219cb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-78bb-a2ac-9232510219cb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-78bb-a2ac-9232510219cb" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-78bb-a2ac-9232510219cb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-78bb-a2ac-9232510219cb" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February2019CreditFacilityMember_019ffbb6-a0bc-737f-8868-aedcf15c56db" xlink:href="bbdc-20260930.xsd#bbdc_February2019CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:to="loc_bbdc_February2019CreditFacilityMember_019ffbb6-a0bc-737f-8868-aedcf15c56db" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member_019ffbb6-a0bc-7970-ac73-481da3bbe0ea" xlink:href="bbdc-20260930.xsd#bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:to="loc_bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member_019ffbb6-a0bc-7970-ac73-481da3bbe0ea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member_019ffbb6-a0bc-7ab9-9c4f-9fa266e87be0" xlink:href="bbdc-20260930.xsd#bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:to="loc_bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member_019ffbb6-a0bc-7ab9-9c4f-9fa266e87be0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member_019ffbb6-a0bc-73aa-b1cd-6f5904149a27" xlink:href="bbdc-20260930.xsd#bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:to="loc_bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member_019ffbb6-a0bc-73aa-b1cd-6f5904149a27" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_November2026NotesMember_019ffbb6-a0bc-7097-bc24-ae765ff228db" xlink:href="bbdc-20260930.xsd#bbdc_November2026NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:to="loc_bbdc_November2026NotesMember_019ffbb6-a0bc-7097-bc24-ae765ff228db" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February2029NotesMember_019ffbb6-a0bc-7ef7-8195-5d3b3fd5fd25" xlink:href="bbdc-20260930.xsd#bbdc_February2029NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:to="loc_bbdc_February2029NotesMember_019ffbb6-a0bc-7ef7-8195-5d3b3fd5fd25" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_September2028NotesMember_019ffbb6-a0bc-7b1a-8147-a3bc513a4b12" xlink:href="bbdc-20260930.xsd#bbdc_September2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-756d-87cc-ab6e33593954" xlink:to="loc_bbdc_September2028NotesMember_019ffbb6-a0bc-7b1a-8147-a3bc513a4b12" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a0bc-7a9b-9846-b273e014976f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-78b1-bd8f-45afb8e180a6" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a0bc-7a9b-9846-b273e014976f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-7a9b-9846-b273e014976f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a0bc-7a9b-9846-b273e014976f" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-7a9b-9846-b273e014976f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-7976-b49b-f00ec7e604d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a0bc-7a9b-9846-b273e014976f" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-7976-b49b-f00ec7e604d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019ffbb6-a0bc-75c3-996c-916ed408356e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-7976-b49b-f00ec7e604d3" xlink:to="loc_us-gaap_LineOfCreditMember_019ffbb6-a0bc-75c3-996c-916ed408356e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_019ffbb6-a0bc-74b1-a54f-aa6d6bd0e5ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-7976-b49b-f00ec7e604d3" xlink:to="loc_us-gaap_SeniorNotesMember_019ffbb6-a0bc-74b1-a54f-aa6d6bd0e5ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_019ffbb6-a0bc-7d13-96bd-299a78e78b89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-76a8-b09a-4b861ced79b8" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_019ffbb6-a0bc-7d13-96bd-299a78e78b89" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019ffbb6-a0bc-730a-8fd6-f543677f7f25" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-76a8-b09a-4b861ced79b8" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019ffbb6-a0bc-730a-8fd6-f543677f7f25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019ffbb6-a0bc-7b27-bfdf-d318272fbd87" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-76a8-b09a-4b861ced79b8" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_019ffbb6-a0bc-7b27-bfdf-d318272fbd87" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_019ffbb6-a0bc-7c21-9373-02070a70b749" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredFinanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-76a8-b09a-4b861ced79b8" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_019ffbb6-a0bc-7c21-9373-02070a70b749" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_019ffbb6-a0bc-77ca-b25e-5bb4bd46ab2e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-76a8-b09a-4b861ced79b8" xlink:to="loc_us-gaap_LongTermDebt_019ffbb6-a0bc-77ca-b25e-5bb4bd46ab2e" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/BORROWINGSAdditionalInformationDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#BORROWINGSAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/BORROWINGSAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-7cdf-aa1b-7eea45a528fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:to="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-7cdf-aa1b-7eea45a528fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdf-aa1b-7eea45a528fe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-7cdf-aa1b-7eea45a528fe" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdf-aa1b-7eea45a528fe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-7cdf-aa1b-7eea45a528fe" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February2019CreditFacilityMember_019ffbb6-a0bc-77b5-8fb6-f5c69a2572ab" xlink:href="bbdc-20260930.xsd#bbdc_February2019CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_February2019CreditFacilityMember_019ffbb6-a0bc-77b5-8fb6-f5c69a2572ab" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_November132025CreditFacilityMember_019ffbb6-a0bc-7f34-930b-5b537ce00643" xlink:href="bbdc-20260930.xsd#bbdc_November132025CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_November132025CreditFacilityMember_019ffbb6-a0bc-7f34-930b-5b537ce00643" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BorrowingsDenominatedInUSDollarsUnderFebruary2019CreditFacilityMember_019ffbb6-a0bc-7e50-8c3a-da7611a67595" xlink:href="bbdc-20260930.xsd#bbdc_BorrowingsDenominatedInUSDollarsUnderFebruary2019CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_BorrowingsDenominatedInUSDollarsUnderFebruary2019CreditFacilityMember_019ffbb6-a0bc-7e50-8c3a-da7611a67595" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BorrowingsDenominatedInCanadianDollarsUnderFebruary2019CreditFacilityMember_019ffbb6-a0bc-7e48-83e8-fd8a74c51595" xlink:href="bbdc-20260930.xsd#bbdc_BorrowingsDenominatedInCanadianDollarsUnderFebruary2019CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_BorrowingsDenominatedInCanadianDollarsUnderFebruary2019CreditFacilityMember_019ffbb6-a0bc-7e48-83e8-fd8a74c51595" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BorrowingsDenominatedInEuroUnderFebruary2019CreditFacilityMember_019ffbb6-a0bc-7f93-a1c3-1771fff587a0" xlink:href="bbdc-20260930.xsd#bbdc_BorrowingsDenominatedInEuroUnderFebruary2019CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_BorrowingsDenominatedInEuroUnderFebruary2019CreditFacilityMember_019ffbb6-a0bc-7f93-a1c3-1771fff587a0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BorrowingsDenominatedInEurounderFebruary2019CreditFacilityMember_019ffbb6-a0bc-7ba9-bea4-c071c477daa3" xlink:href="bbdc-20260930.xsd#bbdc_BorrowingsDenominatedInEurounderFebruary2019CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_BorrowingsDenominatedInEurounderFebruary2019CreditFacilityMember_019ffbb6-a0bc-7ba9-bea4-c071c477daa3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesASeniorUnsecuredNotesDueAugust2025Member_019ffbb6-a0bc-7965-af7c-ad28f57a660a" xlink:href="bbdc-20260930.xsd#bbdc_SeriesASeniorUnsecuredNotesDueAugust2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_SeriesASeniorUnsecuredNotesDueAugust2025Member_019ffbb6-a0bc-7965-af7c-ad28f57a660a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesBSeniorUnsecuredNotesDueNovember2025Member_019ffbb6-a0bc-7aa2-94cf-b1671605bbac" xlink:href="bbdc-20260930.xsd#bbdc_SeriesBSeniorUnsecuredNotesDueNovember2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_SeriesBSeniorUnsecuredNotesDueNovember2025Member_019ffbb6-a0bc-7aa2-94cf-b1671605bbac" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member_019ffbb6-a0bc-7c25-95a9-caf8afffa7c9" xlink:href="bbdc-20260930.xsd#bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member_019ffbb6-a0bc-7c25-95a9-caf8afffa7c9" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesBAndSeriesCSeniorUnsecuredNotesDueNovemberMember_019ffbb6-a0bc-75ac-acae-0d537fa81887" xlink:href="bbdc-20260930.xsd#bbdc_SeriesBAndSeriesCSeniorUnsecuredNotesDueNovemberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_SeriesBAndSeriesCSeniorUnsecuredNotesDueNovemberMember_019ffbb6-a0bc-75ac-acae-0d537fa81887" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member_019ffbb6-a0bc-76b7-af73-f4d58c5a0452" xlink:href="bbdc-20260930.xsd#bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member_019ffbb6-a0bc-76b7-af73-f4d58c5a0452" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member_019ffbb6-a0bc-78c2-9e92-1a65912507ef" xlink:href="bbdc-20260930.xsd#bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member_019ffbb6-a0bc-78c2-9e92-1a65912507ef" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesDAndSeriesESeniorUnsecuredNotesDueFebruaryMember_019ffbb6-a0bc-72f1-a4de-8fbb307f3ab0" xlink:href="bbdc-20260930.xsd#bbdc_SeriesDAndSeriesESeniorUnsecuredNotesDueFebruaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_SeriesDAndSeriesESeniorUnsecuredNotesDueFebruaryMember_019ffbb6-a0bc-72f1-a4de-8fbb307f3ab0" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_November2026NotesMember_019ffbb6-a0bc-778f-a6fc-ecec01c34582" xlink:href="bbdc-20260930.xsd#bbdc_November2026NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_November2026NotesMember_019ffbb6-a0bc-778f-a6fc-ecec01c34582" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February2029NotesMember_019ffbb6-a0bc-795e-801f-34725f856b16" xlink:href="bbdc-20260930.xsd#bbdc_February2029NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_February2029NotesMember_019ffbb6-a0bc-795e-801f-34725f856b16" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_September2028NotesMember_019ffbb6-a0bc-75d9-830e-4e988ab830a2" xlink:href="bbdc-20260930.xsd#bbdc_September2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7cdc-98ce-93ea293f32af" xlink:to="loc_bbdc_September2028NotesMember_019ffbb6-a0bc-75d9-830e-4e988ab830a2" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a0bc-7104-b6ca-80234cb67d96" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a0bc-7104-b6ca-80234cb67d96" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-7104-b6ca-80234cb67d96_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a0bc-7104-b6ca-80234cb67d96" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-7104-b6ca-80234cb67d96_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-73ca-bf22-61b930bae68c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019ffbb6-a0bc-7104-b6ca-80234cb67d96" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-73ca-bf22-61b930bae68c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019ffbb6-a0bc-73ed-8735-e1ab26e36c11" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-73ca-bf22-61b930bae68c" xlink:to="loc_us-gaap_LineOfCreditMember_019ffbb6-a0bc-73ed-8735-e1ab26e36c11" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_019ffbb6-a0bc-7572-8c9e-9a5b9abfe198" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019ffbb6-a0bc-73ca-bf22-61b930bae68c" xlink:to="loc_us-gaap_SeniorNotesMember_019ffbb6-a0bc-7572-8c9e-9a5b9abfe198" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_019ffbb6-a0bc-7e14-ab4d-c0fddcb09012" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:to="loc_us-gaap_VariableRateAxis_019ffbb6-a0bc-7e14-ab4d-c0fddcb09012" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7e14-ab4d-c0fddcb09012_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_019ffbb6-a0bc-7e14-ab4d-c0fddcb09012" xlink:to="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7e14-ab4d-c0fddcb09012_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_019ffbb6-a0bc-7e14-ab4d-c0fddcb09012" xlink:to="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredOvernightFinancingRateSofrMember_019ffbb6-a0bc-7669-a9a9-dff36a5778e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredOvernightFinancingRateSofrMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_us-gaap_SecuredOvernightFinancingRateSofrMember_019ffbb6-a0bc-7669-a9a9-dff36a5778e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ApplicableCurrencyRateMember_019ffbb6-a0bc-781e-89b3-f545d031a79c" xlink:href="bbdc-20260930.xsd#bbdc_ApplicableCurrencyRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_bbdc_ApplicableCurrencyRateMember_019ffbb6-a0bc-781e-89b3-f545d031a79c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BaseRateMember_019ffbb6-a0bc-7305-8d63-df384b640401" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BaseRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_us-gaap_BaseRateMember_019ffbb6-a0bc-7305-8d63-df384b640401" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_AustralianBenchmarkRateMember_019ffbb6-a0bc-7d55-bcdc-7f9e0984fc4c" xlink:href="bbdc-20260930.xsd#bbdc_AustralianBenchmarkRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_bbdc_AustralianBenchmarkRateMember_019ffbb6-a0bc-7d55-bcdc-7f9e0984fc4c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ScreenRateMember_019ffbb6-a0bc-7e9e-bc0e-d05b0264833c" xlink:href="bbdc-20260930.xsd#bbdc_ScreenRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_bbdc_ScreenRateMember_019ffbb6-a0bc-7e9e-bc0e-d05b0264833c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalFundsPurchasedMember_019ffbb6-a0bc-71c8-b8e5-77c0cacf3c9b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FederalFundsPurchasedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_us-gaap_FederalFundsPurchasedMember_019ffbb6-a0bc-71c8-b8e5-77c0cacf3c9b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_OvernightBankFundingRateMember_019ffbb6-a0bc-74c1-990b-f6a1d5a15740" xlink:href="bbdc-20260930.xsd#bbdc_OvernightBankFundingRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_bbdc_OvernightBankFundingRateMember_019ffbb6-a0bc-74c1-990b-f6a1d5a15740" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_OneMonthSecuredOvernightFinancingRateSOFRMember_019ffbb6-a0bc-7738-b182-e23e6061ea85" xlink:href="bbdc-20260930.xsd#bbdc_OneMonthSecuredOvernightFinancingRateSOFRMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_bbdc_OneMonthSecuredOvernightFinancingRateSOFRMember_019ffbb6-a0bc-7738-b182-e23e6061ea85" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_CORRAMember_019ffbb6-a0bc-703f-8941-2871104f9bd5" xlink:href="bbdc-20260930.xsd#bbdc_CORRAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_bbdc_CORRAMember_019ffbb6-a0bc-703f-8941-2871104f9bd5" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_EuroInterbankOfferedRateEURIBORMember_019ffbb6-a0bc-778e-99bb-8f1ccf593695" xlink:href="bbdc-20260930.xsd#bbdc_EuroInterbankOfferedRateEURIBORMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_019ffbb6-a0bc-7f87-a09f-887498671853" xlink:to="loc_bbdc_EuroInterbankOfferedRateEURIBORMember_019ffbb6-a0bc-778e-99bb-8f1ccf593695" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingAxis_019ffbb6-a0bc-70e8-b2f5-be80914f6929" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExternalCreditRatingByGroupingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingAxis_019ffbb6-a0bc-70e8-b2f5-be80914f6929" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingDomain_019ffbb6-a0bc-70e8-b2f5-be80914f6929_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExternalCreditRatingByGroupingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingAxis_019ffbb6-a0bc-70e8-b2f5-be80914f6929" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingDomain_019ffbb6-a0bc-70e8-b2f5-be80914f6929_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingByGroupingDomain_019ffbb6-a0bc-7a07-8360-dd7a6491e544" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExternalCreditRatingByGroupingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingAxis_019ffbb6-a0bc-70e8-b2f5-be80914f6929" xlink:to="loc_us-gaap_ExternalCreditRatingByGroupingDomain_019ffbb6-a0bc-7a07-8360-dd7a6491e544" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExternalCreditRatingInvestmentGradeMember_019ffbb6-a0bc-75e3-a7f9-8398944b3ed2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExternalCreditRatingInvestmentGradeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ExternalCreditRatingByGroupingDomain_019ffbb6-a0bc-7a07-8360-dd7a6491e544" xlink:to="loc_us-gaap_ExternalCreditRatingInvestmentGradeMember_019ffbb6-a0bc-75e3-a7f9-8398944b3ed2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InterestPeriodAxis_019ffbb6-a0bc-730a-911b-5558814b42d9" xlink:href="bbdc-20260930.xsd#bbdc_InterestPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:to="loc_bbdc_InterestPeriodAxis_019ffbb6-a0bc-730a-911b-5558814b42d9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InterestPeriodDomain_019ffbb6-a0bc-730a-911b-5558814b42d9_default" xlink:href="bbdc-20260930.xsd#bbdc_InterestPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_bbdc_InterestPeriodAxis_019ffbb6-a0bc-730a-911b-5558814b42d9" xlink:to="loc_bbdc_InterestPeriodDomain_019ffbb6-a0bc-730a-911b-5558814b42d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InterestPeriodDomain_019ffbb6-a0bc-794e-8778-84b5bd11903b" xlink:href="bbdc-20260930.xsd#bbdc_InterestPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_bbdc_InterestPeriodAxis_019ffbb6-a0bc-730a-911b-5558814b42d9" xlink:to="loc_bbdc_InterestPeriodDomain_019ffbb6-a0bc-794e-8778-84b5bd11903b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InterestPeriodOfOneMonthMember_019ffbb6-a0bc-71c5-ab2c-4e4fd387c1f2" xlink:href="bbdc-20260930.xsd#bbdc_InterestPeriodOfOneMonthMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_InterestPeriodDomain_019ffbb6-a0bc-794e-8778-84b5bd11903b" xlink:to="loc_bbdc_InterestPeriodOfOneMonthMember_019ffbb6-a0bc-71c5-ab2c-4e4fd387c1f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InterestPeriodOfThreeMonthMember_019ffbb6-a0bc-731e-ac17-3a719e2aab33" xlink:href="bbdc-20260930.xsd#bbdc_InterestPeriodOfThreeMonthMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_InterestPeriodDomain_019ffbb6-a0bc-794e-8778-84b5bd11903b" xlink:to="loc_bbdc_InterestPeriodOfThreeMonthMember_019ffbb6-a0bc-731e-ac17-3a719e2aab33" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_InterestPeriodOfSixMonthMember_019ffbb6-a0bc-7bbf-9560-d90334dc9453" xlink:href="bbdc-20260930.xsd#bbdc_InterestPeriodOfSixMonthMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_bbdc_InterestPeriodDomain_019ffbb6-a0bc-794e-8778-84b5bd11903b" xlink:to="loc_bbdc_InterestPeriodOfSixMonthMember_019ffbb6-a0bc-7bbf-9560-d90334dc9453" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-75f9-8beb-8b402d6947fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-75f9-8beb-8b402d6947fe" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-75f9-8beb-8b402d6947fe_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-75f9-8beb-8b402d6947fe" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-75f9-8beb-8b402d6947fe_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7ad8-8a56-e2b295487d5b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019ffbb6-a0bc-75f9-8beb-8b402d6947fe" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7ad8-8a56-e2b295487d5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019ffbb6-a0bc-7063-aaec-d2a0a9676dbe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019ffbb6-a0bc-7ad8-8a56-e2b295487d5b" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019ffbb6-a0bc-7063-aaec-d2a0a9676dbe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7ee0-a529-71ed6bb23e85" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019ffbb6-a0bc-7615-af58-52f0485a9e6f" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7ee0-a529-71ed6bb23e85" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7ee0-a529-71ed6bb23e85_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7ee0-a529-71ed6bb23e85" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7ee0-a529-71ed6bb23e85_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7fd1-8a67-e64206937cd6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7ee0-a529-71ed6bb23e85" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7fd1-8a67-e64206937cd6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_019ffbb6-a0bc-7f95-90bf-94df39d96991" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7fd1-8a67-e64206937cd6" xlink:to="loc_us-gaap_InterestRateSwapMember_019ffbb6-a0bc-7f95-90bf-94df39d96991" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019ffbb6-a0bc-75ed-a00b-c5e6b170b5ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019ffbb6-a0bc-75ed-a00b-c5e6b170b5ec" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_LineOfCreditFacilityAccordionFeatureAggregateLimit_019ffbb6-a0bc-76d1-b155-ee0a77e0daee" xlink:href="bbdc-20260930.xsd#bbdc_LineOfCreditFacilityAccordionFeatureAggregateLimit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_LineOfCreditFacilityAccordionFeatureAggregateLimit_019ffbb6-a0bc-76d1-b155-ee0a77e0daee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_LineOfCreditRepaymentPeriodAfterMaturity_019ffbb6-a0bc-7454-9c60-cb86c78713b3" xlink:href="bbdc-20260930.xsd#bbdc_LineOfCreditRepaymentPeriodAfterMaturity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_LineOfCreditRepaymentPeriodAfterMaturity_019ffbb6-a0bc-7454-9c60-cb86c78713b3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_019ffbb6-a0bc-743a-8204-4707d0bc9e34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_019ffbb6-a0bc-743a-8204-4707d0bc9e34" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtInstrumentCreditSpreadAdjustment_019ffbb6-a0bc-7376-a9dd-f51df38c32a5" xlink:href="bbdc-20260930.xsd#bbdc_DebtInstrumentCreditSpreadAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_DebtInstrumentCreditSpreadAdjustment_019ffbb6-a0bc-7376-a9dd-f51df38c32a5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_LineOfCreditFacilityChangeInReallocationOfCommitments_019ffbb6-a0bc-7b56-9754-6a0fbffef822" xlink:href="bbdc-20260930.xsd#bbdc_LineOfCreditFacilityChangeInReallocationOfCommitments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_LineOfCreditFacilityChangeInReallocationOfCommitments_019ffbb6-a0bc-7b56-9754-6a0fbffef822" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_019ffbb6-a0bc-722f-9397-f38dd282a766" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfLongTermLinesOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_019ffbb6-a0bc-722f-9397-f38dd282a766" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtInstrumentVariableInterestRateFloor_019ffbb6-a0bc-78e6-9e0d-3211d0eb46f7" xlink:href="bbdc-20260930.xsd#bbdc_DebtInstrumentVariableInterestRateFloor"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_DebtInstrumentVariableInterestRateFloor_019ffbb6-a0bc-78e6-9e0d-3211d0eb46f7" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_019ffbb6-a0bc-7172-a8dc-43b459d919b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_019ffbb6-a0bc-7172-a8dc-43b459d919b0" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtIssuanceCostsLineOfCreditArrangementsGross_019ffbb6-a0bc-7e4a-8bac-9e1187e165a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtIssuanceCostsLineOfCreditArrangementsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DebtIssuanceCostsLineOfCreditArrangementsGross_019ffbb6-a0bc-7e4a-8bac-9e1187e165a9" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_019ffbb6-a0bc-7c4d-bd98-dfd2f03fbf05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_LineOfCredit_019ffbb6-a0bc-7c4d-bd98-dfd2f03fbf05" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_019ffbb6-a0bc-73be-9e46-d6127d7957f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_019ffbb6-a0bc-73be-9e46-d6127d7957f7" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_019ffbb6-a0bc-7ff8-935e-acfba58bacf1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_LongTermDebtFairValue_019ffbb6-a0bc-7ff8-935e-acfba58bacf1" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_019ffbb6-a0bc-7725-80d9-5063c2ade6cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_019ffbb6-a0bc-7725-80d9-5063c2ade6cd" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019ffbb6-a0bc-75a1-be14-c28c96a2668e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019ffbb6-a0bc-75a1-be14-c28c96a2668e" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_LineOfCreditInterestRateStepUpIncreasePursuantToInvestmentGradeConditions_019ffbb6-a0bc-7bcf-adb5-45323d021035" xlink:href="bbdc-20260930.xsd#bbdc_LineOfCreditInterestRateStepUpIncreasePursuantToInvestmentGradeConditions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_LineOfCreditInterestRateStepUpIncreasePursuantToInvestmentGradeConditions_019ffbb6-a0bc-7bcf-adb5-45323d021035" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_LineOfCreditInterestRateStepUpToIncreasePursuantToDebtToTotalAssetsThreshold_019ffbb6-a0bc-7292-a4df-0db3a8034954" xlink:href="bbdc-20260930.xsd#bbdc_LineOfCreditInterestRateStepUpToIncreasePursuantToDebtToTotalAssetsThreshold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_LineOfCreditInterestRateStepUpToIncreasePursuantToDebtToTotalAssetsThreshold_019ffbb6-a0bc-7292-a4df-0db3a8034954" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_019ffbb6-a0bc-716e-ac91-d5fbe993abf1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPricePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_019ffbb6-a0bc-716e-ac91-d5fbe993abf1" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ProceedsFromIssuanceOfSeniorLongTermDebtNet_019ffbb6-a0bc-7414-bb77-beff0c9c0b81" xlink:href="bbdc-20260930.xsd#bbdc_ProceedsFromIssuanceOfSeniorLongTermDebtNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_ProceedsFromIssuanceOfSeniorLongTermDebtNet_019ffbb6-a0bc-7414-bb77-beff0c9c0b81" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-a0bc-7f5c-8ff2-51b0d3889b09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-a0bc-7f5c-8ff2-51b0d3889b09" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFixedInterestRate_019ffbb6-a0bc-7c51-92a2-ab8acd8324e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFixedInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DerivativeFixedInterestRate_019ffbb6-a0bc-7c51-92a2-ab8acd8324e2" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeVariableInterestRate_019ffbb6-a0bc-70a6-b850-31f6b4e40c9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeVariableInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DerivativeVariableInterestRate_019ffbb6-a0bc-70a6-b850-31f6b4e40c9d" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019ffbb6-a0bc-714e-a623-20e60a65b560" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DerivativeAssets_019ffbb6-a0bc-714e-a623-20e60a65b560" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019ffbb6-a0bc-7630-9e0d-832ff60e9318" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_us-gaap_DerivativeLiabilities_019ffbb6-a0bc-7630-9e0d-832ff60e9318" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtInstrumentOwnershipPercentageForImmediateConversion_019ffbb6-a0bc-7e4d-80b3-3c1f5939d2f4" xlink:href="bbdc-20260930.xsd#bbdc_DebtInstrumentOwnershipPercentageForImmediateConversion"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019ffbb6-a0bc-7463-a428-bc55c5968a21" xlink:to="loc_bbdc_DebtInstrumentOwnershipPercentageForImmediateConversion_019ffbb6-a0bc-7e4d-80b3-3c1f5939d2f4" xlink:type="arc" order="24"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSAdditionalinformationDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#DERIVATIVEINSTRUMENTSAdditionalinformationDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSAdditionalinformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7ac2-be66-78aff10925f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7fcc-a1e6-b89c159802f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7ac2-be66-78aff10925f2" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7fcc-a1e6-b89c159802f2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7587-91fd-bf6715b2cfba" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7fcc-a1e6-b89c159802f2" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7587-91fd-bf6715b2cfba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7587-91fd-bf6715b2cfba_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7587-91fd-bf6715b2cfba" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7587-91fd-bf6715b2cfba_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7f1b-a36e-254956e72dc0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7587-91fd-bf6715b2cfba" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7f1b-a36e-254956e72dc0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BaringsLLCMember_019ffbb6-a0bc-79a6-813e-54b3045fcaac" xlink:href="bbdc-20260930.xsd#bbdc_BaringsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7f1b-a36e-254956e72dc0" xlink:to="loc_bbdc_BaringsLLCMember_019ffbb6-a0bc-79a6-813e-54b3045fcaac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7ab4-890d-bafbc26d64bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7fcc-a1e6-b89c159802f2" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7ab4-890d-bafbc26d64bc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7ab4-890d-bafbc26d64bc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7ab4-890d-bafbc26d64bc" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7ab4-890d-bafbc26d64bc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-718b-970f-daa9dc08ae8f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7ab4-890d-bafbc26d64bc" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-718b-970f-daa9dc08ae8f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MVCCreditSupportAgreementMember_019ffbb6-a0bc-7756-a1df-5b68e1446356" xlink:href="bbdc-20260930.xsd#bbdc_MVCCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-718b-970f-daa9dc08ae8f" xlink:to="loc_bbdc_MVCCreditSupportAgreementMember_019ffbb6-a0bc-7756-a1df-5b68e1446356" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a0bc-7dd3-b568-c47c77eb6ac3" xlink:href="bbdc-20260930.xsd#bbdc_PriorSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-718b-970f-daa9dc08ae8f" xlink:to="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a0bc-7dd3-b568-c47c77eb6ac3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-a0bc-7337-92c7-f15e40285d56" xlink:href="bbdc-20260930.xsd#bbdc_NewSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-718b-970f-daa9dc08ae8f" xlink:to="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-a0bc-7337-92c7-f15e40285d56" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019ffbb6-a0bc-778c-8f5c-83f4cd3d9a1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-718b-970f-daa9dc08ae8f" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019ffbb6-a0bc-778c-8f5c-83f4cd3d9a1d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-a0bc-75a1-90e0-76196f095b89" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7ac2-be66-78aff10925f2" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-a0bc-75a1-90e0-76196f095b89" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTermOfContract_019ffbb6-a0bc-722b-b14f-d3e036210508" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTermOfContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7ac2-be66-78aff10925f2" xlink:to="loc_us-gaap_DerivativeTermOfContract_019ffbb6-a0bc-722b-b14f-d3e036210508" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019ffbb6-a0bc-78b8-a86f-f75490cd86a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7ac2-be66-78aff10925f2" xlink:to="loc_us-gaap_DerivativeAssets_019ffbb6-a0bc-78b8-a86f-f75490cd86a9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-a0bc-7169-b165-e0d1645f2aad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7ac2-be66-78aff10925f2" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-a0bc-7169-b165-e0d1645f2aad" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSScheduleofFairValueandAggregateUnrealizedAppreciationDepreciationDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#DERIVATIVEINSTRUMENTSScheduleofFairValueandAggregateUnrealizedAppreciationDepreciationDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSScheduleofFairValueandAggregateUnrealizedAppreciationDepreciationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7b2d-a356-616eb00abe1e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-788a-b194-20d058ee9228" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7b2d-a356-616eb00abe1e" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-788a-b194-20d058ee9228" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7b78-95e9-477147dacb8f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-788a-b194-20d058ee9228" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7b78-95e9-477147dacb8f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7b78-95e9-477147dacb8f_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7b78-95e9-477147dacb8f" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7b78-95e9-477147dacb8f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7637-ba6c-4805592975a7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7b78-95e9-477147dacb8f" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7637-ba6c-4805592975a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BaringsLLCMember_019ffbb6-a0bc-7426-86bd-743e27b5b473" xlink:href="bbdc-20260930.xsd#bbdc_BaringsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7637-ba6c-4805592975a7" xlink:to="loc_bbdc_BaringsLLCMember_019ffbb6-a0bc-7426-86bd-743e27b5b473" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7b42-b1ce-b3ef2d9e8f73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-788a-b194-20d058ee9228" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7b42-b1ce-b3ef2d9e8f73" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7b42-b1ce-b3ef2d9e8f73_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7b42-b1ce-b3ef2d9e8f73" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7b42-b1ce-b3ef2d9e8f73_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-71c4-b9cd-5c0db292dc42" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-7b42-b1ce-b3ef2d9e8f73" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-71c4-b9cd-5c0db292dc42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a0bc-7bef-a06b-f97dfae992fb" xlink:href="bbdc-20260930.xsd#bbdc_PriorSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-71c4-b9cd-5c0db292dc42" xlink:to="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a0bc-7bef-a06b-f97dfae992fb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-a0bc-7c1c-954e-6b3f2f9ed2ce" xlink:href="bbdc-20260930.xsd#bbdc_NewSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-71c4-b9cd-5c0db292dc42" xlink:to="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-a0bc-7c1c-954e-6b3f2f9ed2ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-a0bc-7e70-9f8d-b27c18928591" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7b2d-a356-616eb00abe1e" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019ffbb6-a0bc-7e70-9f8d-b27c18928591" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019ffbb6-a0bc-7e51-8b7f-db3b6b5cba70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7b2d-a356-616eb00abe1e" xlink:to="loc_us-gaap_DerivativeAssets_019ffbb6-a0bc-7e51-8b7f-db3b6b5cba70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ffbb6-a0bc-75a7-885f-940e0ab251d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossOnDerivatives"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-7b2d-a356-616eb00abe1e" xlink:to="loc_us-gaap_UnrealizedGainLossOnDerivatives_019ffbb6-a0bc-75a7-885f-940e0ab251d5" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSScheduleofSignificantUnobservableInputsusedinValuationDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#DERIVATIVEINSTRUMENTSScheduleofSignificantUnobservableInputsusedinValuationDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSScheduleofSignificantUnobservableInputsusedinValuationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019ffbb6-a0bc-7d10-bb38-50ce372a9283" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019ffbb6-a0bc-77bd-ba2d-8f9126e0af41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019ffbb6-a0bc-7d10-bb38-50ce372a9283" xlink:to="loc_us-gaap_DerivativeTable_019ffbb6-a0bc-77bd-ba2d-8f9126e0af41" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7b54-9aba-bae479b4890b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ffbb6-a0bc-77bd-ba2d-8f9126e0af41" xlink:to="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7b54-9aba-bae479b4890b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7b54-9aba-bae479b4890b_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7b54-9aba-bae479b4890b" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7b54-9aba-bae479b4890b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7ef2-95d6-ddc8f066f7f6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019ffbb6-a0bc-7b54-9aba-bae479b4890b" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7ef2-95d6-ddc8f066f7f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_BaringsLLCMember_019ffbb6-a0bc-7d8e-9584-1854dfa01673" xlink:href="bbdc-20260930.xsd#bbdc_BaringsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019ffbb6-a0bc-7ef2-95d6-ddc8f066f7f6" xlink:to="loc_bbdc_BaringsLLCMember_019ffbb6-a0bc-7d8e-9584-1854dfa01673" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-76a4-a547-49c3ede57b56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ffbb6-a0bc-77bd-ba2d-8f9126e0af41" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-76a4-a547-49c3ede57b56" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-76a4-a547-49c3ede57b56_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-76a4-a547-49c3ede57b56" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-76a4-a547-49c3ede57b56_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-79cc-9262-613e7f877b86" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-76a4-a547-49c3ede57b56" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-79cc-9262-613e7f877b86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a0bc-7817-9da3-4cc327e6ed33" xlink:href="bbdc-20260930.xsd#bbdc_PriorSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-79cc-9262-613e7f877b86" xlink:to="loc_bbdc_PriorSierraCreditSupportAgreementMember_019ffbb6-a0bc-7817-9da3-4cc327e6ed33" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-a0bc-7b74-a74b-0e6e5f17f6e4" xlink:href="bbdc-20260930.xsd#bbdc_NewSierraCreditSupportAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-79cc-9262-613e7f877b86" xlink:to="loc_bbdc_NewSierraCreditSupportAgreementMember_019ffbb6-a0bc-7b74-a74b-0e6e5f17f6e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019ffbb6-a0bc-7235-a393-fae8f51a45cf" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ffbb6-a0bc-77bd-ba2d-8f9126e0af41" xlink:to="loc_srt_RangeAxis_019ffbb6-a0bc-7235-a393-fae8f51a45cf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ffbb6-a0bc-7235-a393-fae8f51a45cf_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019ffbb6-a0bc-7235-a393-fae8f51a45cf" xlink:to="loc_srt_RangeMember_019ffbb6-a0bc-7235-a393-fae8f51a45cf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019ffbb6-a0bc-7577-9676-99a052d3e1dc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019ffbb6-a0bc-7235-a393-fae8f51a45cf" xlink:to="loc_srt_RangeMember_019ffbb6-a0bc-7577-9676-99a052d3e1dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019ffbb6-a0bc-702f-86aa-cecac9098745" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ffbb6-a0bc-7577-9676-99a052d3e1dc" xlink:to="loc_srt_MinimumMember_019ffbb6-a0bc-702f-86aa-cecac9098745" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019ffbb6-a0bc-79bf-8598-2773d34a8ebf" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ffbb6-a0bc-7577-9676-99a052d3e1dc" xlink:to="loc_srt_MaximumMember_019ffbb6-a0bc-79bf-8598-2773d34a8ebf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_WeightedAverageMember_019ffbb6-a0bc-77f5-a3db-cb83373f2687" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_WeightedAverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019ffbb6-a0bc-7577-9676-99a052d3e1dc" xlink:to="loc_srt_WeightedAverageMember_019ffbb6-a0bc-77f5-a3db-cb83373f2687" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_019ffbb6-a0bc-7fd4-befc-c30824030c7d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ffbb6-a0bc-77bd-ba2d-8f9126e0af41" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_019ffbb6-a0bc-7fd4-befc-c30824030c7d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7fd4-befc-c30824030c7d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019ffbb6-a0bc-7fd4-befc-c30824030c7d" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7fd4-befc-c30824030c7d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7bc6-bc82-6fd56b8b0661" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019ffbb6-a0bc-7fd4-befc-c30824030c7d" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7bc6-bc82-6fd56b8b0661" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputEnterpriseValueMember_019ffbb6-a0bc-7ec4-8165-bac3b87553d4" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputEnterpriseValueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7bc6-bc82-6fd56b8b0661" xlink:to="loc_bbdc_MeasurementInputEnterpriseValueMember_019ffbb6-a0bc-7ec4-8165-bac3b87553d4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputAssetVolatilityMember_019ffbb6-a0bc-7394-9851-500b657ffcb1" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputAssetVolatilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7bc6-bc82-6fd56b8b0661" xlink:to="loc_bbdc_MeasurementInputAssetVolatilityMember_019ffbb6-a0bc-7394-9851-500b657ffcb1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputTimeUntilExitMember_019ffbb6-a0bc-722a-b594-138f69edbb0a" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputTimeUntilExitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7bc6-bc82-6fd56b8b0661" xlink:to="loc_bbdc_MeasurementInputTimeUntilExitMember_019ffbb6-a0bc-722a-b594-138f69edbb0a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputDiscountRateMember_019ffbb6-a0bc-70a9-8a09-225b3d9c5063" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputDiscountRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7bc6-bc82-6fd56b8b0661" xlink:to="loc_us-gaap_MeasurementInputDiscountRateMember_019ffbb6-a0bc-70a9-8a09-225b3d9c5063" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_MeasurementInputRecoveryRateMember_019ffbb6-a0bc-74f0-be50-e5942c0493d0" xlink:href="bbdc-20260930.xsd#bbdc_MeasurementInputRecoveryRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019ffbb6-a0bc-7bc6-bc82-6fd56b8b0661" xlink:to="loc_bbdc_MeasurementInputRecoveryRateMember_019ffbb6-a0bc-74f0-be50-e5942c0493d0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-7f12-a1aa-6d2f27138498" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019ffbb6-a0bc-77bd-ba2d-8f9126e0af41" xlink:to="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-7f12-a1aa-6d2f27138498" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7f12-a1aa-6d2f27138498_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-7f12-a1aa-6d2f27138498" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-7f12-a1aa-6d2f27138498_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-77ec-b369-2c057b132427" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationTechniqueAxis_019ffbb6-a0bc-7f12-a1aa-6d2f27138498" xlink:to="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-77ec-b369-2c057b132427" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ValuationSimulationAnalysisMember_019ffbb6-a0bc-7b06-b9c5-b187e9428992" xlink:href="bbdc-20260930.xsd#bbdc_ValuationSimulationAnalysisMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-77ec-b369-2c057b132427" xlink:to="loc_bbdc_ValuationSimulationAnalysisMember_019ffbb6-a0bc-7b06-b9c5-b187e9428992" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BlackScholesMertonModelMember_019ffbb6-a0bc-73e8-945c-5584049cb26a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BlackScholesMertonModelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationTechniqueDomain_019ffbb6-a0bc-77ec-b369-2c057b132427" xlink:to="loc_us-gaap_BlackScholesMertonModelMember_019ffbb6-a0bc-73e8-945c-5584049cb26a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019ffbb6-a0bc-71e2-8add-10f95ee68687" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ffbb6-a0bc-7d10-bb38-50ce372a9283" xlink:to="loc_us-gaap_DerivativeAssets_019ffbb6-a0bc-71e2-8add-10f95ee68687" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetMeasurementInput_019ffbb6-a0bc-7988-8a11-f13a2470d117" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019ffbb6-a0bc-7d10-bb38-50ce372a9283" xlink:to="loc_us-gaap_DerivativeAssetMeasurementInput_019ffbb6-a0bc-7988-8a11-f13a2470d117" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSScheduleofForeignCurrencyForwardContractsDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#DERIVATIVEINSTRUMENTSScheduleofForeignCurrencyForwardContractsDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSScheduleofForeignCurrencyForwardContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7ef8-baa8-b03412a6e358" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7ef8-baa8-b03412a6e358" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OpenForwardForeignCurrencyContractIdentifierAxis_019ffbb6-a0bc-7095-8ac2-c840faff860f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OpenForwardForeignCurrencyContractIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7ef8-baa8-b03412a6e358" xlink:to="loc_us-gaap_OpenForwardForeignCurrencyContractIdentifierAxis_019ffbb6-a0bc-7095-8ac2-c840faff860f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-722a-8b49-322935b882de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7ef8-baa8-b03412a6e358" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-722a-8b49-322935b882de" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-722a-8b49-322935b882de_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-722a-8b49-322935b882de" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-722a-8b49-322935b882de_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7031-aac9-be8c204cc569" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-722a-8b49-322935b882de" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7031-aac9-be8c204cc569" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019ffbb6-a0bc-7d86-afe4-b8e2229d3c7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7031-aac9-be8c204cc569" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019ffbb6-a0bc-7d86-afe4-b8e2229d3c7a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ffbb6-a0bc-79be-9706-58f77e42bdda" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ffbb6-a0bc-79be-9706-58f77e42bdda" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount_019ffbb6-a0bc-709d-9e97-aa59d9d4d43a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeAssetNotionalAmount_019ffbb6-a0bc-709d-9e97-aa59d9d4d43a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019ffbb6-a0bc-7e40-8cd6-4726060b9887" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019ffbb6-a0bc-7e40-8cd6-4726060b9887" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019ffbb6-a0bc-7145-b80b-97426a6c84fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019ffbb6-a0bc-7145-b80b-97426a6c84fe" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-a0bc-7f67-8ecd-a9d05456ac97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-a0bc-7f67-8ecd-a9d05456ac97" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSScheduleofForeignCurrencyForwardContractsDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#DERIVATIVEINSTRUMENTSScheduleofForeignCurrencyForwardContractsDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/DERIVATIVEINSTRUMENTSScheduleofForeignCurrencyForwardContractsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7ef8-baa8-b03412a6e358" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7ef8-baa8-b03412a6e358" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-722a-8b49-322935b882de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_019ffbb6-a0bc-7ef8-baa8-b03412a6e358" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-722a-8b49-322935b882de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-722a-8b49-322935b882de_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-722a-8b49-322935b882de" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-722a-8b49-322935b882de_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7031-aac9-be8c204cc569" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019ffbb6-a0bc-722a-8b49-322935b882de" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7031-aac9-be8c204cc569" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeContractMember_019ffbb6-a0bc-7d86-afe4-b8e2229d3c7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019ffbb6-a0bc-7031-aac9-be8c204cc569" xlink:to="loc_us-gaap_ForeignExchangeContractMember_019ffbb6-a0bc-7d86-afe4-b8e2229d3c7a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ffbb6-a0bc-79be-9706-58f77e42bdda" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilityNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeLiabilityNotionalAmount_019ffbb6-a0bc-79be-9706-58f77e42bdda" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount_019ffbb6-a0bc-709d-9e97-aa59d9d4d43a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeAssetNotionalAmount_019ffbb6-a0bc-709d-9e97-aa59d9d4d43a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019ffbb6-a0bc-7e40-8cd6-4726060b9887" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossLiability_019ffbb6-a0bc-7e40-8cd6-4726060b9887" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019ffbb6-a0bc-7145-b80b-97426a6c84fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement_019ffbb6-a0bc-7145-b80b-97426a6c84fe" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-a0bc-7f67-8ecd-a9d05456ac97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_019ffbb6-a0bc-70f1-af32-730f691077ae" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019ffbb6-a0bc-7f67-8ecd-a9d05456ac97" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/COMMITMENTSANDCONTINGENCIESScheduleofBalancesofUnusedCommitmentstoExtendFinancingDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#COMMITMENTSANDCONTINGENCIESScheduleofBalancesofUnusedCommitmentstoExtendFinancingDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/COMMITMENTSANDCONTINGENCIESScheduleofBalancesofUnusedCommitmentstoExtendFinancingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bc-78ff-a8e6-633e9dce8a2c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-7958-a241-7217db71151a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfGuaranteeObligationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bc-78ff-a8e6-633e9dce8a2c" xlink:to="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-7958-a241-7217db71151a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-70f5-a396-a5ecb8de625f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIdentifierAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-7958-a241-7217db71151a" xlink:to="loc_us-gaap_InvestmentIdentifierAxis_019ffbb6-a0bc-70f5-a396-a5ecb8de625f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a0bc-7a7c-bb3c-8612489d7c5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bc-78ff-a8e6-633e9dce8a2c" xlink:to="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a0bc-7a7c-bb3c-8612489d7c5c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/COMMITMENTSANDCONTINGENCIESScheduleofBalancesofUnusedCommitmentstoExtendFinancingDetails_1" xlink:type="simple" xlink:href="bbdc-20260930.xsd#COMMITMENTSANDCONTINGENCIESScheduleofBalancesofUnusedCommitmentstoExtendFinancingDetails_1"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/COMMITMENTSANDCONTINGENCIESScheduleofBalancesofUnusedCommitmentstoExtendFinancingDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bc-78ff-a8e6-633e9dce8a2c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-7958-a241-7217db71151a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfGuaranteeObligationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bc-78ff-a8e6-633e9dce8a2c" xlink:to="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-7958-a241-7217db71151a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a0bc-7a7c-bb3c-8612489d7c5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bc-78ff-a8e6-633e9dce8a2c" xlink:to="loc_us-gaap_InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount_019ffbb6-a0bc-7a7c-bb3c-8612489d7c5c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/COMMITMENTSANDCONTINGENCIESAdditionalinformationDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#COMMITMENTSANDCONTINGENCIESAdditionalinformationDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/COMMITMENTSANDCONTINGENCIESAdditionalinformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bd-7b23-994b-40659cdda58e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-73be-80b3-8c6002991b73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfGuaranteeObligationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bd-7b23-994b-40659cdda58e" xlink:to="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-73be-80b3-8c6002991b73" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-7571-b4ff-4b41b93bb903" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-73be-80b3-8c6002991b73" xlink:to="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-7571-b4ff-4b41b93bb903" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7571-b4ff-4b41b93bb903_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-7571-b4ff-4b41b93bb903" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-7571-b4ff-4b41b93bb903_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-73e7-89c3-ced10d18756a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019ffbb6-a0bc-7571-b4ff-4b41b93bb903" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-73e7-89c3-ced10d18756a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SantanderBankAndMVCAutomotiveGroupGmbHMember_019ffbb6-a0bc-7bb1-9eba-b98483b7345a" xlink:href="bbdc-20260930.xsd#bbdc_SantanderBankAndMVCAutomotiveGroupGmbHMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-73e7-89c3-ced10d18756a" xlink:to="loc_bbdc_SantanderBankAndMVCAutomotiveGroupGmbHMember_019ffbb6-a0bc-7bb1-9eba-b98483b7345a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_ErsteBankAndMCVAutomotiveGroupGmbhMember_019ffbb6-a0bc-784a-b2b2-20249ccac91a" xlink:href="bbdc-20260930.xsd#bbdc_ErsteBankAndMCVAutomotiveGroupGmbhMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019ffbb6-a0bc-73e7-89c3-ced10d18756a" xlink:to="loc_bbdc_ErsteBankAndMCVAutomotiveGroupGmbhMember_019ffbb6-a0bc-784a-b2b2-20249ccac91a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsByNatureAxis_019ffbb6-a0bc-752b-94a7-c2ab70a33e12" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsByNatureAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGuaranteeObligationsTable_019ffbb6-a0bc-73be-80b3-8c6002991b73" xlink:to="loc_us-gaap_GuaranteeObligationsByNatureAxis_019ffbb6-a0bc-752b-94a7-c2ab70a33e12" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain_019ffbb6-a0bc-752b-94a7-c2ab70a33e12_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis_019ffbb6-a0bc-752b-94a7-c2ab70a33e12" xlink:to="loc_us-gaap_GuaranteeObligationsNatureDomain_019ffbb6-a0bc-752b-94a7-c2ab70a33e12_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain_019ffbb6-a0bd-7af4-82c6-4a55bdc65b39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsNatureDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis_019ffbb6-a0bc-752b-94a7-c2ab70a33e12" xlink:to="loc_us-gaap_GuaranteeObligationsNatureDomain_019ffbb6-a0bd-7af4-82c6-4a55bdc65b39" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialGuaranteeMember_019ffbb6-a0bd-7515-b3a0-758c6b6d4dcb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialGuaranteeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsNatureDomain_019ffbb6-a0bd-7af4-82c6-4a55bdc65b39" xlink:to="loc_us-gaap_FinancialGuaranteeMember_019ffbb6-a0bd-7515-b3a0-758c6b6d4dcb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue_019ffbb6-a0bd-7301-8fa5-4279ee49214a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsCurrentCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GuaranteeObligationsLineItems_019ffbb6-a0bd-7b23-994b-40659cdda58e" xlink:to="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue_019ffbb6-a0bd-7301-8fa5-4279ee49214a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://ir.barings.com/role/SUBSEQUENTEVENTSDetails" xlink:type="simple" xlink:href="bbdc-20260930.xsd#SUBSEQUENTEVENTSDetails"/>
  <link:definitionLink xlink:role="http://ir.barings.com/role/SUBSEQUENTEVENTSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_019ffbb6-a0bd-7ec1-8ca4-a055a699a7a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_019ffbb6-a0bd-7642-aa0a-b7fdbf3ef9e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_019ffbb6-a0bd-7ec1-8ca4-a055a699a7a7" xlink:to="loc_us-gaap_SubsequentEventTable_019ffbb6-a0bd-7642-aa0a-b7fdbf3ef9e1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_019ffbb6-a0bd-7f43-b4d1-427799d9a368" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_019ffbb6-a0bd-7642-aa0a-b7fdbf3ef9e1" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_019ffbb6-a0bd-7f43-b4d1-427799d9a368" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019ffbb6-a0bd-7f43-b4d1-427799d9a368_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019ffbb6-a0bd-7f43-b4d1-427799d9a368" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019ffbb6-a0bd-7f43-b4d1-427799d9a368_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019ffbb6-a0bd-7a0f-8abe-2cf8fd8f8231" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019ffbb6-a0bd-7f43-b4d1-427799d9a368" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019ffbb6-a0bd-7a0f-8abe-2cf8fd8f8231" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_019ffbb6-a0bd-72a3-bef7-df9429241cbe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_019ffbb6-a0bd-7a0f-8abe-2cf8fd8f8231" xlink:to="loc_us-gaap_SubsequentEventMember_019ffbb6-a0bd-72a3-bef7-df9429241cbe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_019ffbb6-a0bd-75fc-9587-1ea73025e97a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockDividendsPerShareDeclared"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_019ffbb6-a0bd-7ec1-8ca4-a055a699a7a7" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_019ffbb6-a0bd-75fc-9587-1ea73025e97a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" xlink:type="simple" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-roles-2026.xsd#eedm1"/>
  <link:definitionLink xlink:role="http://fasb.org/srt/role/srt-eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperatingPaidInKind" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeOperatingPaidInKind"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_InterestIncomeOperatingPaidInKind" xlink:type="arc" order="691"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOperating" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_InterestExpenseOperating" xlink:type="arc" order="692"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_DebtAndEquitySecuritiesRealizedGainLossBeforeDistributions_019ffbb6-86ba-7fb9-8b6e-5b31b88782dd" xlink:href="bbdc-20260930.xsd#bbdc_DebtAndEquitySecuritiesRealizedGainLossBeforeDistributions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_bbdc_DebtAndEquitySecuritiesRealizedGainLossBeforeDistributions_019ffbb6-86ba-7fb9-8b6e-5b31b88782dd" xlink:type="arc" order="693"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="loc_us-gaap_DebtAndEquitySecuritiesUnrealizedGainLoss" xlink:type="arc" order="694"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://xbrl.sec.gov/cef/role/SecurityOnly" xlink:type="simple" xlink:href="https://xbrl.sec.gov/cef/2026/cef-2026.xsd#SecurityOnly"/>
  <link:definitionLink xlink:role="http://xbrl.sec.gov/cef/role/SecurityOnly" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February2019CreditFacilityMember_019ffbb6-86ba-72cf-b2bd-68b733205495" xlink:href="bbdc-20260930.xsd#bbdc_February2019CreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_February2019CreditFacilityMember_019ffbb6-86ba-72cf-b2bd-68b733205495" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesASeniorUnsecuredNotesDueAugust2025Member_019ffbb6-8754-7e46-ac0a-50b2ec5c3a23" xlink:href="bbdc-20260930.xsd#bbdc_SeriesASeniorUnsecuredNotesDueAugust2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_SeriesASeniorUnsecuredNotesDueAugust2025Member_019ffbb6-8754-7e46-ac0a-50b2ec5c3a23" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesBAndSeriesCSeniorUnsecuredNotesDueNovemberMember_019ffbb6-8889-7d3b-80ca-d3bd3b360fa4" xlink:href="bbdc-20260930.xsd#bbdc_SeriesBAndSeriesCSeniorUnsecuredNotesDueNovemberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_SeriesBAndSeriesCSeniorUnsecuredNotesDueNovemberMember_019ffbb6-8889-7d3b-80ca-d3bd3b360fa4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesBSeniorUnsecuredNotesDueNovember2025Member_019ffbb6-86ba-77da-90a5-8bcdfb39b0c3" xlink:href="bbdc-20260930.xsd#bbdc_SeriesBSeniorUnsecuredNotesDueNovember2025Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_SeriesBSeniorUnsecuredNotesDueNovember2025Member_019ffbb6-86ba-77da-90a5-8bcdfb39b0c3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member_019ffbb6-86ba-7eb7-b575-4bdf8ec2ec3d" xlink:href="bbdc-20260930.xsd#bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_SeriesCSeniorUnsecuredNotesDueNovember2027Member_019ffbb6-86ba-7eb7-b575-4bdf8ec2ec3d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_FebruaryNotesMember_019ffbb6-87ef-72c2-a648-6bca8849dd80" xlink:href="bbdc-20260930.xsd#bbdc_FebruaryNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_FebruaryNotesMember_019ffbb6-87ef-72c2-a648-6bca8849dd80" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member_019ffbb6-86ba-7d56-9683-16426ffe6b6c" xlink:href="bbdc-20260930.xsd#bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_SeriesDSeniorUnsecuredNotesDueFebruary2026Member_019ffbb6-86ba-7d56-9683-16426ffe6b6c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member_019ffbb6-86ba-7f6b-9a00-d4cfdc1f2ab1" xlink:href="bbdc-20260930.xsd#bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_SeriesESeniorUnsecuredNotesDueFebruary2028Member_019ffbb6-86ba-7f6b-9a00-d4cfdc1f2ab1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_November2026NotesMember_019ffbb6-86ba-7509-b48f-441eb3a51197" xlink:href="bbdc-20260930.xsd#bbdc_November2026NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_November2026NotesMember_019ffbb6-86ba-7509-b48f-441eb3a51197" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_February2029NotesMember_019ffbb6-86ba-72c1-9f06-f12322e09e27" xlink:href="bbdc-20260930.xsd#bbdc_February2029NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_February2029NotesMember_019ffbb6-86ba-72c1-9f06-f12322e09e27" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_bbdc_September2028NotesMember_019ffbb6-86ba-7807-823f-955f07b24182" xlink:href="bbdc-20260930.xsd#bbdc_September2028NotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="loc_bbdc_September2028NotesMember_019ffbb6-86ba-7807-823f-955f07b24182" xlink:type="arc" order="11"/>
  </link:definitionLink>
</link:linkbase>
