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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019fd756-cffe-70f3-a4d7-d8dfa0dd7dde,g:f95ab9b2-2350-4202-aef3-0b0c6cd600f6-->
<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://www.svcreit.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETS" xlink:type="simple" xlink:href="svc-20260930.xsd#CONDENSEDCONSOLIDATEDBALANCESHEETS"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETS" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019fd756-d1be-7974-b8e3-545fe1274a9e" 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_019fd756-d1be-71aa-981f-e278b626da01" 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_019fd756-d1be-7974-b8e3-545fe1274a9e" xlink:to="loc_us-gaap_StatementTable_019fd756-d1be-71aa-981f-e278b626da01" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7f5b-bcd2-b6cc108ad54b" 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_StatementTable_019fd756-d1be-71aa-981f-e278b626da01" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7f5b-bcd2-b6cc108ad54b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7f5b-bcd2-b6cc108ad54b_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_019fd756-d1be-7f5b-bcd2-b6cc108ad54b" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7f5b-bcd2-b6cc108ad54b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7a8e-ae88-5ebbdefde986" 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_019fd756-d1be-7f5b-bcd2-b6cc108ad54b" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7a8e-ae88-5ebbdefde986" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonrelatedPartyMember_019fd756-d1be-7dd4-81fe-81ade9d10e80" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonrelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7a8e-ae88-5ebbdefde986" xlink:to="loc_us-gaap_NonrelatedPartyMember_019fd756-d1be-7dd4-81fe-81ade9d10e80" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019fd756-d1be-76ac-8c68-5e4ed2c0437a" 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_019fd756-d1be-7a8e-ae88-5ebbdefde986" xlink:to="loc_us-gaap_RelatedPartyMember_019fd756-d1be-76ac-8c68-5e4ed2c0437a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" 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_019fd756-d1be-7974-b8e3-545fe1274a9e" xlink:to="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateInvestmentPropertyNetAbstract_019fd756-d1be-72b8-9587-0875392410b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateInvestmentPropertyNetAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_RealEstateInvestmentPropertyNetAbstract_019fd756-d1be-72b8-9587-0875392410b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Land_019fd756-d1be-7878-9310-8674e2e65d05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Land"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstateInvestmentPropertyNetAbstract_019fd756-d1be-72b8-9587-0875392410b8" xlink:to="loc_us-gaap_Land_019fd756-d1be-7878-9310-8674e2e65d05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_InvestmentBuildingImprovementsAndEquipment_019fd756-d1be-73bd-87ec-1c675161c3b4" xlink:href="svc-20260930.xsd#svc_InvestmentBuildingImprovementsAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstateInvestmentPropertyNetAbstract_019fd756-d1be-72b8-9587-0875392410b8" xlink:to="loc_svc_InvestmentBuildingImprovementsAndEquipment_019fd756-d1be-73bd-87ec-1c675161c3b4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateInvestmentPropertyAtCost_019fd756-d1be-76af-9337-0bb5b5e58efd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateInvestmentPropertyAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstateInvestmentPropertyNetAbstract_019fd756-d1be-72b8-9587-0875392410b8" xlink:to="loc_us-gaap_RealEstateInvestmentPropertyAtCost_019fd756-d1be-76af-9337-0bb5b5e58efd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation_019fd756-d1be-70d6-bb95-fb0530c158aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstateInvestmentPropertyNetAbstract_019fd756-d1be-72b8-9587-0875392410b8" xlink:to="loc_us-gaap_RealEstateInvestmentPropertyAccumulatedDepreciation_019fd756-d1be-70d6-bb95-fb0530c158aa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateInvestmentPropertyNet_019fd756-d1be-7e23-b2ce-dca870d37bc9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateInvestmentPropertyNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstateInvestmentPropertyNetAbstract_019fd756-d1be-72b8-9587-0875392410b8" xlink:to="loc_us-gaap_RealEstateInvestmentPropertyNet_019fd756-d1be-7e23-b2ce-dca870d37bc9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019fd756-d1be-79bb-850c-f224094e0976" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_EquityMethodInvestments_019fd756-d1be-79bb-850c-f224094e0976" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019fd756-d1be-7f09-ad38-a8e16ba3f7a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019fd756-d1be-7f09-ad38-a8e16ba3f7a5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup_019fd756-d1be-78f9-9edd-8e8a885666b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup_019fd756-d1be-78f9-9edd-8e8a885666b7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019fd756-d1be-7430-bd4f-a6f7783ca940" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019fd756-d1be-7430-bd4f-a6f7783ca940" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCash_019fd756-d1be-743d-b1f7-9a0caf41442e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_RestrictedCash_019fd756-d1be-743d-b1f7-9a0caf41442e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivables_019fd756-d1be-7305-9251-6efae7bc9ffd" 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_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_OtherReceivables_019fd756-d1be-7305-9251-6efae7bc9ffd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets_019fd756-d1be-7fe0-8240-117ef99153e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_OtherAssets_019fd756-d1be-7fe0-8240-117ef99153e8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019fd756-d1be-79f3-8a4a-bb289eafd4fe" 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_019fd756-d1be-7946-a612-d6bebab3bb87" xlink:to="loc_us-gaap_Assets_019fd756-d1be-79f3-8a4a-bb289eafd4fe" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019fd756-d1be-7974-b8e3-545fe1274a9e" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuredDebt_019fd756-d1be-7da6-ac9f-1a29be58e9b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuredDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:to="loc_us-gaap_SecuredDebt_019fd756-d1be-7da6-ac9f-1a29be58e9b6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnsecuredDebt_019fd756-d1be-7857-991a-361ed6f32403" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnsecuredDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:to="loc_us-gaap_UnsecuredDebt_019fd756-d1be-7857-991a-361ed6f32403" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilities_019fd756-d1be-7f94-9753-86f800a32796" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:to="loc_us-gaap_OtherLiabilities_019fd756-d1be-7f94-9753-86f800a32796" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_019fd756-d1be-7537-bf83-662b662948d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_019fd756-d1be-7537-bf83-662b662948d8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019fd756-d1be-7af7-b506-ec7a3e1473ed" 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_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:to="loc_us-gaap_Liabilities_019fd756-d1be-7af7-b506-ec7a3e1473ed" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_019fd756-d1be-78bd-a6d6-68c5e8e7b679" 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_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:to="loc_us-gaap_CommitmentsAndContingencies_019fd756-d1be-78bd-a6d6-68c5e8e7b679" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityAbstract_019fd756-d1be-7027-8d33-4effc6cb3dd3" 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_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:to="loc_us-gaap_StockholdersEquityAbstract_019fd756-d1be-7027-8d33-4effc6cb3dd3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_019fd756-d1be-75a0-a23c-775559cd3be5" 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_019fd756-d1be-7027-8d33-4effc6cb3dd3" xlink:to="loc_us-gaap_CommonStockValue_019fd756-d1be-75a0-a23c-775559cd3be5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_019fd756-d1be-781b-8854-541b2959d0d2" 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_019fd756-d1be-7027-8d33-4effc6cb3dd3" xlink:to="loc_us-gaap_AdditionalPaidInCapital_019fd756-d1be-781b-8854-541b2959d0d2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019fd756-d1be-75eb-a407-e9f892cd46a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019fd756-d1be-7027-8d33-4effc6cb3dd3" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019fd756-d1be-75eb-a407-e9f892cd46a1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019fd756-d1be-772f-a08c-86e1bffddc47" 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_019fd756-d1be-7027-8d33-4effc6cb3dd3" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019fd756-d1be-772f-a08c-86e1bffddc47" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_CumulativeCommonStockDistributions_019fd756-d1be-7d48-826b-8fe48ac254ac" xlink:href="svc-20260930.xsd#svc_CumulativeCommonStockDistributions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019fd756-d1be-7027-8d33-4effc6cb3dd3" xlink:to="loc_svc_CumulativeCommonStockDistributions_019fd756-d1be-7d48-826b-8fe48ac254ac" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019fd756-d1be-7126-a6e6-149922517756" 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_019fd756-d1be-7027-8d33-4effc6cb3dd3" xlink:to="loc_us-gaap_StockholdersEquity_019fd756-d1be-7126-a6e6-149922517756" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fd756-d1be-7009-9ab8-0e01c128ebe2" 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_LiabilitiesAndStockholdersEquityAbstract_019fd756-d1be-7536-b47b-670ce9eaa509" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_019fd756-d1be-7009-9ab8-0e01c128ebe2" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY" xlink:type="simple" xlink:href="svc-20260930.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019fd756-d1be-7597-8c95-b51c9e4a6c2d" 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_019fd756-d1be-7e53-85e2-6f1e3ed70c8e" 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_019fd756-d1be-7597-8c95-b51c9e4a6c2d" xlink:to="loc_us-gaap_StatementTable_019fd756-d1be-7e53-85e2-6f1e3ed70c8e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019fd756-d1be-71bd-a179-a4a86f7ef95a" 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_019fd756-d1be-7e53-85e2-6f1e3ed70c8e" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019fd756-d1be-71bd-a179-a4a86f7ef95a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019fd756-d1be-71bd-a179-a4a86f7ef95a_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_019fd756-d1be-71bd-a179-a4a86f7ef95a" xlink:to="loc_us-gaap_EquityComponentDomain_019fd756-d1be-71bd-a179-a4a86f7ef95a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019fd756-d1be-7d87-8bb0-b5ee3c351314" 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_019fd756-d1be-71bd-a179-a4a86f7ef95a" xlink:to="loc_us-gaap_EquityComponentDomain_019fd756-d1be-7d87-8bb0-b5ee3c351314" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019fd756-d1be-78b0-91a7-563be433de8a" 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_019fd756-d1be-7d87-8bb0-b5ee3c351314" xlink:to="loc_us-gaap_CommonStockMember_019fd756-d1be-78b0-91a7-563be433de8a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_CumulativeCommonDistributionsMember_019fd756-d1be-7af1-a238-4d1bf450cc2e" xlink:href="svc-20260930.xsd#svc_CumulativeCommonDistributionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019fd756-d1be-7d87-8bb0-b5ee3c351314" xlink:to="loc_svc_CumulativeCommonDistributionsMember_019fd756-d1be-7af1-a238-4d1bf450cc2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019fd756-d1be-723c-a841-3d21c27c0e07" 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_019fd756-d1be-7d87-8bb0-b5ee3c351314" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019fd756-d1be-723c-a841-3d21c27c0e07" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019fd756-d1be-7743-967e-6882aafdab4a" 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_019fd756-d1be-7d87-8bb0-b5ee3c351314" xlink:to="loc_us-gaap_RetainedEarningsMember_019fd756-d1be-7743-967e-6882aafdab4a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019fd756-d1be-797b-9247-4074d7973161" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019fd756-d1be-7d87-8bb0-b5ee3c351314" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019fd756-d1be-797b-9247-4074d7973161" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019fd756-d1be-7597-8c95-b51c9e4a6c2d" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_019fd756-d1be-7fe1-96fb-844978b4a07c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_SharesOutstanding_019fd756-d1be-7fe1-96fb-844978b4a07c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019fd756-d1be-7787-b990-6892f2eac79d" 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_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_StockholdersEquity_019fd756-d1be-7787-b990-6892f2eac79d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019fd756-d1be-7b2c-a607-5bc8ec174f0b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_NetIncomeLoss_019fd756-d1be-7b2c-a607-5bc8ec174f0b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_019fd756-d1be-7888-be3b-2c32b6c3c257" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_019fd756-d1be-7888-be3b-2c32b6c3c257" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_019fd756-d1be-7670-bcb7-a12c0446ace2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_019fd756-d1be-7670-bcb7-a12c0446ace2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciEquityMethodInvestmentAfterTax_019fd756-d1be-758d-a6a0-c5fa5a4f8434" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OciEquityMethodInvestmentAfterTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_OciEquityMethodInvestmentAfterTax_019fd756-d1be-758d-a6a0-c5fa5a4f8434" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_019fd756-d1be-79c4-8cf3-684280a514ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_019fd756-d1be-79c4-8cf3-684280a514ac" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_019fd756-d1be-731e-a3ed-c40c2ec80541" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_019fd756-d1be-731e-a3ed-c40c2ec80541" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_019fd756-d1be-71de-a0ad-0728d1149856" 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_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_019fd756-d1be-71de-a0ad-0728d1149856" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_019fd756-d1be-7ccd-94e9-b110cc42ba3e" 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_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_019fd756-d1be-7ccd-94e9-b110cc42ba3e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_StockForfeitedDuringPeriodShares_019fd756-d1be-7bb0-8e12-295844c52d86" xlink:href="svc-20260930.xsd#svc_StockForfeitedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_svc_StockForfeitedDuringPeriodShares_019fd756-d1be-7bb0-8e12-295844c52d86" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_StockForfeitedDuringPeriodValues_019fd756-d1be-7692-b1cd-72ad3d9052fd" xlink:href="svc-20260930.xsd#svc_StockForfeitedDuringPeriodValues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_svc_StockForfeitedDuringPeriodValues_019fd756-d1be-7692-b1cd-72ad3d9052fd" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019fd756-d1be-7a1c-b58f-d0f805ae1102" 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_IncreaseDecreaseInStockholdersEquityRollForward_019fd756-d1be-7149-8b59-5d8cec808ebd" xlink:to="loc_us-gaap_Dividends_019fd756-d1be-7a1c-b58f-d0f805ae1102" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_019fd756-d1be-7e11-b3f1-bf2e1e652ec0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019fd756-d1be-73cf-824d-da54da63728d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/OrganizationandBasisofPresentationDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#OrganizationandBasisofPresentationDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/OrganizationandBasisofPresentationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-716c-934d-2bf25f2e74ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstatePropertiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7f24-add4-10b40e8a921a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRealEstatePropertiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-716c-934d-2bf25f2e74ac" xlink:to="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7f24-add4-10b40e8a921a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7701-8901-ae368bcf84c4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7f24-add4-10b40e8a921a" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7701-8901-ae368bcf84c4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7701-8901-ae368bcf84c4_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7701-8901-ae368bcf84c4" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7701-8901-ae368bcf84c4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7bde-a10d-dcf23d0c5d7f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7701-8901-ae368bcf84c4" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7bde-a10d-dcf23d0c5d7f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_019fd756-d1be-7c5e-8d55-1f807c537ecc" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7bde-a10d-dcf23d0c5d7f" xlink:to="loc_svc_NetLeasePropertyMember_019fd756-d1be-7c5e-8d55-1f807c537ecc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-7528-a024-b3adc8d80561" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7bde-a10d-dcf23d0c5d7f" xlink:to="loc_srt_HotelMember_019fd756-d1be-7528-a024-b3adc8d80561" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_019fd756-d1be-789a-bf16-10c89e47a2d8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7f24-add4-10b40e8a921a" xlink:to="loc_srt_ConsolidatedEntitiesAxis_019fd756-d1be-789a-bf16-10c89e47a2d8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019fd756-d1be-789a-bf16-10c89e47a2d8_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019fd756-d1be-789a-bf16-10c89e47a2d8" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019fd756-d1be-789a-bf16-10c89e47a2d8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019fd756-d1be-73f6-9575-d19f576f4c47" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019fd756-d1be-789a-bf16-10c89e47a2d8" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019fd756-d1be-73f6-9575-d19f576f4c47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_019fd756-d1be-7aad-b280-d39293768979" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_019fd756-d1be-73f6-9575-d19f576f4c47" xlink:to="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_019fd756-d1be-7aad-b280-d39293768979" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7b17-80ac-4f437fc9cd06" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-716c-934d-2bf25f2e74ac" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7b17-80ac-4f437fc9cd06" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OwnershipPercentageHeldInSubsidiary_019fd756-d1be-77b3-9f0a-567c059da17f" xlink:href="svc-20260930.xsd#svc_OwnershipPercentageHeldInSubsidiary"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-716c-934d-2bf25f2e74ac" xlink:to="loc_svc_OwnershipPercentageHeldInSubsidiary_019fd756-d1be-77b3-9f0a-567c059da17f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019fd756-d1be-7e7b-a97f-a53ca3efb54c" 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_RealEstatePropertiesLineItems_019fd756-d1be-716c-934d-2bf25f2e74ac" xlink:to="loc_us-gaap_Assets_019fd756-d1be-7e7b-a97f-a53ca3efb54c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019fd756-d1be-743b-b14a-bfb6513e595c" 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_RealEstatePropertiesLineItems_019fd756-d1be-716c-934d-2bf25f2e74ac" xlink:to="loc_us-gaap_Liabilities_019fd756-d1be-743b-b14a-bfb6513e595c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_019fd756-d1be-752f-b9f1-47ed77125bee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-716c-934d-2bf25f2e74ac" xlink:to="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_019fd756-d1be-752f-b9f1-47ed77125bee" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/RevenueRecognitionDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#RevenueRecognitionDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/RevenueRecognitionDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d1be-76ad-a22a-6f4dcbc7d8f6" 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_019fd756-d1be-7571-83c3-b759af90b1b0" 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_019fd756-d1be-76ad-a22a-6f4dcbc7d8f6" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019fd756-d1be-7571-83c3-b759af90b1b0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7f6a-a78a-c9ddb31decb4" 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_019fd756-d1be-7571-83c3-b759af90b1b0" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7f6a-a78a-c9ddb31decb4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7f6a-a78a-c9ddb31decb4_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_019fd756-d1be-7f6a-a78a-c9ddb31decb4" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7f6a-a78a-c9ddb31decb4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-743e-a630-3413b955b3ff" 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_019fd756-d1be-7f6a-a78a-c9ddb31decb4" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-743e-a630-3413b955b3ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019fd756-d1be-759f-8e64-077832586051" 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_019fd756-d1be-743e-a630-3413b955b3ff" xlink:to="loc_us-gaap_RelatedPartyMember_019fd756-d1be-759f-8e64-077832586051" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StraightLineRent_019fd756-d1be-7d28-ad8a-2b8f6b04bb04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StraightLineRent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d1be-76ad-a22a-6f4dcbc7d8f6" xlink:to="loc_us-gaap_StraightLineRent_019fd756-d1be-7d28-ad8a-2b8f6b04bb04" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_StraightLineRentReceivables_019fd756-d1be-717a-a398-93129e4666b6" xlink:href="svc-20260930.xsd#svc_StraightLineRentReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d1be-76ad-a22a-6f4dcbc7d8f6" xlink:to="loc_svc_StraightLineRentReceivables_019fd756-d1be-717a-a398-93129e4666b6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingLeaseLeaseIncomePercentageRent_019fd756-d1be-7f59-acd4-14fb26acb23b" xlink:href="svc-20260930.xsd#svc_OperatingLeaseLeaseIncomePercentageRent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d1be-76ad-a22a-6f4dcbc7d8f6" xlink:to="loc_svc_OperatingLeaseLeaseIncomePercentageRent_019fd756-d1be-7f59-acd4-14fb26acb23b" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/RealEstatePropertiesNarrativeDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#RealEstatePropertiesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/RealEstatePropertiesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstatePropertiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7625-ad3f-7c65d1b67815" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRealEstatePropertiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7625-ad3f-7c65d1b67815" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7446-a5f0-ce6dd6c2d395" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7625-ad3f-7c65d1b67815" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7446-a5f0-ce6dd6c2d395" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7446-a5f0-ce6dd6c2d395_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7446-a5f0-ce6dd6c2d395" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7446-a5f0-ce6dd6c2d395_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7639-9405-6eeaca6360dc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7446-a5f0-ce6dd6c2d395" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7639-9405-6eeaca6360dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HotelsAndNetLeasePropertiesMember_019fd756-d1be-798c-9bfa-10f7e9104c12" xlink:href="svc-20260930.xsd#svc_HotelsAndNetLeasePropertiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7639-9405-6eeaca6360dc" xlink:to="loc_svc_HotelsAndNetLeasePropertiesMember_019fd756-d1be-798c-9bfa-10f7e9104c12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_019fd756-d1be-7400-babd-84e5be56eeeb" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_HotelsAndNetLeasePropertiesMember_019fd756-d1be-798c-9bfa-10f7e9104c12" xlink:to="loc_svc_NetLeasePropertyMember_019fd756-d1be-7400-babd-84e5be56eeeb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-7504-abf4-10a398fdf852" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_HotelsAndNetLeasePropertiesMember_019fd756-d1be-798c-9bfa-10f7e9104c12" xlink:to="loc_srt_HotelMember_019fd756-d1be-7504-abf4-10a398fdf852" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionAxis_019fd756-d1be-76ac-935b-1852a08305bc" 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_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7625-ad3f-7c65d1b67815" xlink:to="loc_us-gaap_AssetAcquisitionAxis_019fd756-d1be-76ac-935b-1852a08305bc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-76ac-935b-1852a08305bc_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_019fd756-d1be-76ac-935b-1852a08305bc" xlink:to="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-76ac-935b-1852a08305bc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-7ec1-ba23-60e55694b24e" 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_019fd756-d1be-76ac-935b-1852a08305bc" xlink:to="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-7ec1-ba23-60e55694b24e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AcquiredRealEstate2026Member_019fd756-d1be-72db-87ad-bf1aa68a6a00" xlink:href="svc-20260930.xsd#svc_AcquiredRealEstate2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-7ec1-ba23-60e55694b24e" xlink:to="loc_svc_AcquiredRealEstate2026Member_019fd756-d1be-72db-87ad-bf1aa68a6a00" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-795f-9ea6-ebc641822f61" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7625-ad3f-7c65d1b67815" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-795f-9ea6-ebc641822f61" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-795f-9ea6-ebc641822f61_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-795f-9ea6-ebc641822f61" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-795f-9ea6-ebc641822f61_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7de4-9548-4202ba2aec62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-795f-9ea6-ebc641822f61" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7de4-9548-4202ba2aec62" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_019fd756-d1be-7730-8682-51e77ab905ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7de4-9548-4202ba2aec62" xlink:to="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_019fd756-d1be-7730-8682-51e77ab905ed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_019fd756-d1be-7267-837a-370b2d8bfa7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7de4-9548-4202ba2aec62" xlink:to="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_019fd756-d1be-7267-837a-370b2d8bfa7a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DisposalGroupHeldForUseNotDiscontinuedOperationsMember_019fd756-d1be-70dd-8640-df5f0d56eee0" xlink:href="svc-20260930.xsd#svc_DisposalGroupHeldForUseNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7de4-9548-4202ba2aec62" xlink:to="loc_svc_DisposalGroupHeldForUseNotDiscontinuedOperationsMember_019fd756-d1be-70dd-8640-df5f0d56eee0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-72af-a2bc-1e507fc029ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7625-ad3f-7c65d1b67815" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-72af-a2bc-1e507fc029ad" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-72af-a2bc-1e507fc029ad_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-72af-a2bc-1e507fc029ad" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-72af-a2bc-1e507fc029ad_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-71d9-92bf-f5159e8f46ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-72af-a2bc-1e507fc029ad" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-71d9-92bf-f5159e8f46ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateDispositionsMember_019fd756-d1be-7b2a-9842-fe827dfb3b4b" xlink:href="svc-20260930.xsd#svc_RealEstateDispositionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-71d9-92bf-f5159e8f46ab" xlink:to="loc_svc_RealEstateDispositionsMember_019fd756-d1be-7b2a-9842-fe827dfb3b4b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_MarketedRealEstateDispositionsMember_01a17f4d-61ca-7e57-a1a4-b45e1505fecb" xlink:href="svc-20260930.xsd#svc_MarketedRealEstateDispositionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-71d9-92bf-f5159e8f46ab" xlink:to="loc_svc_MarketedRealEstateDispositionsMember_01a17f4d-61ca-7e57-a1a4-b45e1505fecb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_019fd756-d1be-7e13-8b28-9b0dccc6b00c" 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_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-7625-ad3f-7c65d1b67815" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_019fd756-d1be-7e13-8b28-9b0dccc6b00c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-7e13-8b28-9b0dccc6b00c_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_019fd756-d1be-7e13-8b28-9b0dccc6b00c" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-7e13-8b28-9b0dccc6b00c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-72a9-9f25-247addcef94c" 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_019fd756-d1be-7e13-8b28-9b0dccc6b00c" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-72a9-9f25-247addcef94c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_019fd756-d1be-7b19-80c1-dc741cacf91f" 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_019fd756-d1be-72a9-9f25-247addcef94c" xlink:to="loc_us-gaap_SubsequentEventMember_019fd756-d1be-7b19-80c1-dc741cacf91f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7ca7-825d-c3e0b717d0a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7ca7-825d-c3e0b717d0a3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AreaOfRealEstateProperty_019fd756-d1be-7239-8b02-289a53ab6deb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AreaOfRealEstateProperty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_us-gaap_AreaOfRealEstateProperty_019fd756-d1be-7239-8b02-289a53ab6deb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfUnitsInRealEstateProperty_019fd756-d1be-7bfc-867a-c044709d57be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfUnitsInRealEstateProperty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_us-gaap_NumberOfUnitsInRealEstateProperty_019fd756-d1be-7bfc-867a-c044709d57be" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateInvestmentPropertyAndRealEstateHeldForSaleAtCost_019fd756-d1be-788f-ba19-907adb48db31" xlink:href="svc-20260930.xsd#svc_RealEstateInvestmentPropertyAndRealEstateHeldForSaleAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_svc_RealEstateInvestmentPropertyAndRealEstateHeldForSaleAtCost_019fd756-d1be-788f-ba19-907adb48db31" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateHeldforsale_019fd756-d1be-73c3-9335-a49123b7be51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateHeldforsale"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_us-gaap_RealEstateHeldforsale_019fd756-d1be-73c3-9335-a49123b7be51" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-7752-8de7-f624ab6b8029" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForCapitalImprovements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-7752-8de7-f624ab6b8029" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireRealEstate_019fd756-d1be-722e-add2-3e45ae3e0131" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_us-gaap_PaymentsToAcquireRealEstate_019fd756-d1be-722e-add2-3e45ae3e0131" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfRealEstate_019fd756-d1be-794b-95d8-69ee2ffbc365" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7e6b-b83f-e56f8067beaf" xlink:to="loc_us-gaap_ProceedsFromSaleOfRealEstate_019fd756-d1be-794b-95d8-69ee2ffbc365" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/RealEstatePropertiesScheduleofAllocationofPurchasePriceforAcquisitionsBasedonEstimatedFairValueofAcquiredAssetsDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#RealEstatePropertiesScheduleofAllocationofPurchasePriceforAcquisitionsBasedonEstimatedFairValueofAcquiredAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/RealEstatePropertiesScheduleofAllocationofPurchasePriceforAcquisitionsBasedonEstimatedFairValueofAcquiredAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstatePropertiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-71a4-91cc-15773af9f26f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRealEstatePropertiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:to="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-71a4-91cc-15773af9f26f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7b7c-8978-d18cd63d25ed" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-71a4-91cc-15773af9f26f" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7b7c-8978-d18cd63d25ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7b7c-8978-d18cd63d25ed_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7b7c-8978-d18cd63d25ed" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7b7c-8978-d18cd63d25ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7799-8684-525db627bf81" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7b7c-8978-d18cd63d25ed" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7799-8684-525db627bf81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_019fd756-d1be-7c5c-b06f-94bd94430eff" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7799-8684-525db627bf81" xlink:to="loc_svc_NetLeasePropertyMember_019fd756-d1be-7c5c-b06f-94bd94430eff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionAxis_019fd756-d1be-74cf-89bd-984584fc72ea" 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_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-71a4-91cc-15773af9f26f" xlink:to="loc_us-gaap_AssetAcquisitionAxis_019fd756-d1be-74cf-89bd-984584fc72ea" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-74cf-89bd-984584fc72ea_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_019fd756-d1be-74cf-89bd-984584fc72ea" xlink:to="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-74cf-89bd-984584fc72ea_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-7dc5-a4e6-6669b7e3ff61" 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_019fd756-d1be-74cf-89bd-984584fc72ea" xlink:to="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-7dc5-a4e6-6669b7e3ff61" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AcquiredRealEstate2026Member_019fd756-d1be-77ac-ab3e-5cd7238ec816" xlink:href="svc-20260930.xsd#svc_AcquiredRealEstate2026Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetAcquisitionDomain_019fd756-d1be-7dc5-a4e6-6669b7e3ff61" xlink:to="loc_svc_AcquiredRealEstate2026Member_019fd756-d1be-77ac-ab3e-5cd7238ec816" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7182-909e-e9676b4ee22e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7182-909e-e9676b4ee22e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AreaOfRealEstateProperty_019fd756-d1be-7534-b460-665dbf9ae2dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AreaOfRealEstateProperty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:to="loc_us-gaap_AreaOfRealEstateProperty_019fd756-d1be-7534-b460-665dbf9ae2dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PaymentsToAcquireRealEstateGross_019fd756-d1be-7ef8-9a44-475edb195592" xlink:href="svc-20260930.xsd#svc_PaymentsToAcquireRealEstateGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:to="loc_svc_PaymentsToAcquireRealEstateGross_019fd756-d1be-7ef8-9a44-475edb195592" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLand_019fd756-d1be-70e8-9db5-82fedec120fe" xlink:href="svc-20260930.xsd#svc_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLand"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:to="loc_svc_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLand_019fd756-d1be-70e8-9db5-82fedec120fe" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildingsImprovementsAndEquipment_019fd756-d1be-7128-82c2-7728161f0814" xlink:href="svc-20260930.xsd#svc_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildingsImprovementsAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:to="loc_svc_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedBuildingsImprovementsAndEquipment_019fd756-d1be-7128-82c2-7728161f0814" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinitelivedIntangibleAssetsAcquired1_019fd756-d1be-737c-b88c-8a166a14a9cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinitelivedIntangibleAssetsAcquired1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:to="loc_us-gaap_FinitelivedIntangibleAssetsAcquired1_019fd756-d1be-737c-b88c-8a166a14a9cf" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClosingCostsOfAcquiredRealEstate_019fd756-d1be-741e-8f3e-061ba4a54262" xlink:href="svc-20260930.xsd#svc_ClosingCostsOfAcquiredRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-7395-b165-be2bf732e153" xlink:to="loc_svc_ClosingCostsOfAcquiredRealEstate_019fd756-d1be-741e-8f3e-061ba4a54262" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/RealEstatePropertiesScheduleofSaleofPropertiesDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#RealEstatePropertiesScheduleofSaleofPropertiesDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/RealEstatePropertiesScheduleofSaleofPropertiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019fd756-d1be-7dc5-b784-2a62b9fb3dc6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019fd756-d1be-774f-b594-3b5edc352b03" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019fd756-d1be-7dc5-b784-2a62b9fb3dc6" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019fd756-d1be-774f-b594-3b5edc352b03" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-77a6-b0c5-8f575e454a79" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019fd756-d1be-774f-b594-3b5edc352b03" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-77a6-b0c5-8f575e454a79" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-77a6-b0c5-8f575e454a79_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-77a6-b0c5-8f575e454a79" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-77a6-b0c5-8f575e454a79_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7a68-b6fb-b89d7dd2ab87" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-77a6-b0c5-8f575e454a79" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7a68-b6fb-b89d7dd2ab87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-7cec-9d3b-95ad9b9d4c41" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7a68-b6fb-b89d7dd2ab87" xlink:to="loc_srt_HotelMember_019fd756-d1be-7cec-9d3b-95ad9b9d4c41" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_019fd756-d1be-77f5-b9b1-2b025f9b01d8" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7a68-b6fb-b89d7dd2ab87" xlink:to="loc_svc_NetLeasePropertyMember_019fd756-d1be-77f5-b9b1-2b025f9b01d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-747d-bebb-a491165e4e05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019fd756-d1be-774f-b594-3b5edc352b03" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-747d-bebb-a491165e4e05" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-747d-bebb-a491165e4e05_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-747d-bebb-a491165e4e05" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-747d-bebb-a491165e4e05_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7ff6-85b1-0415e1942cd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-747d-bebb-a491165e4e05" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7ff6-85b1-0415e1942cd8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_019fd756-d1be-7fd5-be33-1c0f084f5bbf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7ff6-85b1-0415e1942cd8" xlink:to="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_019fd756-d1be-7fd5-be33-1c0f084f5bbf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-71ab-a63e-8e3cdaed9f18" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019fd756-d1be-774f-b594-3b5edc352b03" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-71ab-a63e-8e3cdaed9f18" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-71ab-a63e-8e3cdaed9f18_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-71ab-a63e-8e3cdaed9f18" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-71ab-a63e-8e3cdaed9f18_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-7d29-b02d-49d9316a159f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-71ab-a63e-8e3cdaed9f18" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-7d29-b02d-49d9316a159f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateDispositionsMember_019fd756-d1be-771e-a4c3-710cb8647ffa" xlink:href="svc-20260930.xsd#svc_RealEstateDispositionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-7d29-b02d-49d9316a159f" xlink:to="loc_svc_RealEstateDispositionsMember_019fd756-d1be-771e-a4c3-710cb8647ffa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-75e4-b107-12dcd879d00f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019fd756-d1be-7dc5-b784-2a62b9fb3dc6" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-75e4-b107-12dcd879d00f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfUnitsInRealEstateProperty_019fd756-d1be-7264-abc6-8f53bfee6adb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfUnitsInRealEstateProperty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019fd756-d1be-7dc5-b784-2a62b9fb3dc6" xlink:to="loc_us-gaap_NumberOfUnitsInRealEstateProperty_019fd756-d1be-7264-abc6-8f53bfee6adb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AreaOfRealEstateProperty_019fd756-d1be-7d1d-bd2e-964f693f6f24" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AreaOfRealEstateProperty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019fd756-d1be-7dc5-b784-2a62b9fb3dc6" xlink:to="loc_us-gaap_AreaOfRealEstateProperty_019fd756-d1be-7d1d-bd2e-964f693f6f24" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfRealEstate_019fd756-d1be-7665-a12c-db87eb0b2aa6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019fd756-d1be-7dc5-b784-2a62b9fb3dc6" xlink:to="loc_us-gaap_ProceedsFromSaleOfRealEstate_019fd756-d1be-7665-a12c-db87eb0b2aa6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfProperties_019fd756-d1be-725f-9562-e504e48e2eef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnSaleOfProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019fd756-d1be-7dc5-b784-2a62b9fb3dc6" xlink:to="loc_us-gaap_GainLossOnSaleOfProperties_019fd756-d1be-725f-9562-e504e48e2eef" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/RealEstatePropertiesScheduleofMajorClassofAssetsandLiabilitiesbyInvestmentsSegmentsDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#RealEstatePropertiesScheduleofMajorClassofAssetsandLiabilitiesbyInvestmentsSegmentsDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/RealEstatePropertiesScheduleofMajorClassofAssetsandLiabilitiesbyInvestmentsSegmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-74aa-aac7-a8557868fa22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstatePropertiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-77cd-ae98-006e0d2332ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRealEstatePropertiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-74aa-aac7-a8557868fa22" xlink:to="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-77cd-ae98-006e0d2332ec" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-70d1-87a4-9f27305a095c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-77cd-ae98-006e0d2332ec" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-70d1-87a4-9f27305a095c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-70d1-87a4-9f27305a095c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-70d1-87a4-9f27305a095c" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-70d1-87a4-9f27305a095c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-79d4-bc92-35f7c9a39a70" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-70d1-87a4-9f27305a095c" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-79d4-bc92-35f7c9a39a70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_019fd756-d1be-74a3-b6f6-44057f5b2ac7" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-79d4-bc92-35f7c9a39a70" xlink:to="loc_svc_NetLeasePropertyMember_019fd756-d1be-74a3-b6f6-44057f5b2ac7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-71f1-83ff-7066154b03e9" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-79d4-bc92-35f7c9a39a70" xlink:to="loc_srt_HotelMember_019fd756-d1be-71f1-83ff-7066154b03e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-7c3b-b583-21ce7f411541" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-77cd-ae98-006e0d2332ec" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-7c3b-b583-21ce7f411541" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7c3b-b583-21ce7f411541_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-7c3b-b583-21ce7f411541" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7c3b-b583-21ce7f411541_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7d74-82b4-e399d640010e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-7c3b-b583-21ce7f411541" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7d74-82b4-e399d640010e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_019fd756-d1be-7891-b083-6535205e0c11" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7d74-82b4-e399d640010e" xlink:to="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_019fd756-d1be-7891-b083-6535205e0c11" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-78db-ae21-ccc9576541cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d1be-77cd-ae98-006e0d2332ec" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-78db-ae21-ccc9576541cc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-78db-ae21-ccc9576541cc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-78db-ae21-ccc9576541cc" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-78db-ae21-ccc9576541cc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-78fe-ac21-b2673a8a25ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-78db-ae21-ccc9576541cc" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-78fe-ac21-b2673a8a25ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateDispositionsMember_019fd756-d1be-7ac0-9d42-985bdddf3eed" xlink:href="svc-20260930.xsd#svc_RealEstateDispositionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-78fe-ac21-b2673a8a25ac" xlink:to="loc_svc_RealEstateDispositionsMember_019fd756-d1be-7ac0-9d42-985bdddf3eed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupAbstract_019fd756-d1be-724b-8914-f7527829bfa5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-74aa-aac7-a8557868fa22" xlink:to="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupAbstract_019fd756-d1be-724b-8914-f7527829bfa5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AssetHeldForSaleNotPartOfDisposalGroupRealEstatePropertiesNet_019fd756-d1be-7a7c-9098-05c0f8f064b2" xlink:href="svc-20260930.xsd#svc_AssetHeldForSaleNotPartOfDisposalGroupRealEstatePropertiesNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupAbstract_019fd756-d1be-724b-8914-f7527829bfa5" xlink:to="loc_svc_AssetHeldForSaleNotPartOfDisposalGroupRealEstatePropertiesNet_019fd756-d1be-7a7c-9098-05c0f8f064b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupOther_019fd756-d1be-79fd-98af-29aa58e0bec3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupAbstract_019fd756-d1be-724b-8914-f7527829bfa5" xlink:to="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupOther_019fd756-d1be-79fd-98af-29aa58e0bec3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup_019fd756-d1be-70bf-ae21-cff4ca4146e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroupAbstract_019fd756-d1be-724b-8914-f7527829bfa5" xlink:to="loc_us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup_019fd756-d1be-70bf-ae21-cff4ca4146e8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_019fd756-d1be-70b7-be17-8ac121d47c41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-74aa-aac7-a8557868fa22" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_019fd756-d1be-70b7-be17-8ac121d47c41" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableAndAccruedLiabilities_019fd756-d1be-7dc7-bebb-ff7bcd060843" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableAndAccruedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_019fd756-d1be-70b7-be17-8ac121d47c41" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableAndAccruedLiabilities_019fd756-d1be-7dc7-bebb-ff7bcd060843" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_019fd756-d1be-72c4-83ca-8e1909187bc3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationAbstract_019fd756-d1be-70b7-be17-8ac121d47c41" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_019fd756-d1be-72c4-83ca-8e1909187bc3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AssetHeldForSaleNotPartOfDisposalGroupOtherWorkingCapital_019fd756-d1be-7b38-93e1-b882e51266bb" xlink:href="svc-20260930.xsd#svc_AssetHeldForSaleNotPartOfDisposalGroupOtherWorkingCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d1be-74aa-aac7-a8557868fa22" xlink:to="loc_svc_AssetHeldForSaleNotPartOfDisposalGroupOtherWorkingCapital_019fd756-d1be-7b38-93e1-b882e51266bb" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/LeasesandManagementAgreementsNarrativeDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#LeasesandManagementAgreementsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/LeasesandManagementAgreementsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7953-b692-4f5e9fde10e4" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-793e-a122-e88005bae6fa" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7953-b692-4f5e9fde10e4" xlink:to="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-793e-a122-e88005bae6fa" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7046-9b42-0ecbad17e4b2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-793e-a122-e88005bae6fa" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7046-9b42-0ecbad17e4b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7046-9b42-0ecbad17e4b2_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7046-9b42-0ecbad17e4b2" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7046-9b42-0ecbad17e4b2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7bcf-bc10-32d55968c74f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7046-9b42-0ecbad17e4b2" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7bcf-bc10-32d55968c74f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_019fd756-d1be-7d98-b680-97e0f343ae1b" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7bcf-bc10-32d55968c74f" xlink:to="loc_svc_NetLeasePropertyMember_019fd756-d1be-7d98-b680-97e0f343ae1b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-79d7-aee8-2b33edb7ab8e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7bcf-bc10-32d55968c74f" xlink:to="loc_srt_HotelMember_019fd756-d1be-79d7-aee8-2b33edb7ab8e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fd756-d1be-74de-b2b7-b9e014230966" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-793e-a122-e88005bae6fa" xlink:to="loc_srt_CounterpartyNameAxis_019fd756-d1be-74de-b2b7-b9e014230966" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-74de-b2b7-b9e014230966_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_019fd756-d1be-74de-b2b7-b9e014230966" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-74de-b2b7-b9e014230966_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c4c-976c-b4b266460ed6" 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_019fd756-d1be-74de-b2b7-b9e014230966" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c4c-976c-b4b266460ed6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_TravelCentersOfAmericaIncMember_019fd756-d1be-7189-85c6-d83e2b3ba10a" xlink:href="svc-20260930.xsd#svc_TravelCentersOfAmericaIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c4c-976c-b4b266460ed6" xlink:to="loc_svc_TravelCentersOfAmericaIncMember_019fd756-d1be-7189-85c6-d83e2b3ba10a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d1be-7448-8924-1d6e80e7ff86" xlink:href="svc-20260930.xsd#svc_SonestaInternationalHotelsCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c4c-976c-b4b266460ed6" xlink:to="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d1be-7448-8924-1d6e80e7ff86" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HyattHotelsCorporationMember_019fd756-d1be-7ba2-a00b-501e7b06fa16" xlink:href="svc-20260930.xsd#svc_HyattHotelsCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c4c-976c-b4b266460ed6" xlink:to="loc_svc_HyattHotelsCorporationMember_019fd756-d1be-7ba2-a00b-501e7b06fa16" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RadissonHospitalityIncMember_019fd756-d1be-7d3e-b981-30a66ca22d3d" xlink:href="svc-20260930.xsd#svc_RadissonHospitalityIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c4c-976c-b4b266460ed6" xlink:to="loc_svc_RadissonHospitalityIncMember_019fd756-d1be-7d3e-b981-30a66ca22d3d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7969-a57f-fbac435950b2" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-793e-a122-e88005bae6fa" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7969-a57f-fbac435950b2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7969-a57f-fbac435950b2_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_019fd756-d1be-7969-a57f-fbac435950b2" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7969-a57f-fbac435950b2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-70e7-b1ca-c2617a549961" 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_019fd756-d1be-7969-a57f-fbac435950b2" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-70e7-b1ca-c2617a549961" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019fd756-d1be-7db6-b612-71bd6b003442" 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_019fd756-d1be-70e7-b1ca-c2617a549961" xlink:to="loc_us-gaap_RelatedPartyMember_019fd756-d1be-7db6-b612-71bd6b003442" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7223-8652-5c3a10370cee" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-793e-a122-e88005bae6fa" xlink:to="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7223-8652-5c3a10370cee" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7223-8652-5c3a10370cee_default" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7223-8652-5c3a10370cee" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7223-8652-5c3a10370cee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7c5e-9a6c-a1a31937a29b" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7223-8652-5c3a10370cee" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7c5e-9a6c-a1a31937a29b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_IHGAgreementMember_019fd756-d1be-7942-8223-78229ca64d5e" xlink:href="svc-20260930.xsd#svc_IHGAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7c5e-9a6c-a1a31937a29b" xlink:to="loc_svc_IHGAgreementMember_019fd756-d1be-7942-8223-78229ca64d5e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7c41-989c-453afc925e45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7953-b692-4f5e9fde10e4" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7c41-989c-453afc925e45" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NumberOfTenants_019fd756-d1be-71fd-b676-19a8b711a1ac" xlink:href="svc-20260930.xsd#svc_NumberOfTenants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7953-b692-4f5e9fde10e4" xlink:to="loc_svc_NumberOfTenants_019fd756-d1be-71fd-b676-19a8b711a1ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NumberOfManagementAgreementsOrLeases_019fd756-d1be-79a1-a644-597e6e498d64" xlink:href="svc-20260930.xsd#svc_NumberOfManagementAgreementsOrLeases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7953-b692-4f5e9fde10e4" xlink:to="loc_svc_NumberOfManagementAgreementsOrLeases_019fd756-d1be-79a1-a644-597e6e498d64" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/LeasesandManagementAgreementsNetLeasePortfolioDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#LeasesandManagementAgreementsNetLeasePortfolioDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/LeasesandManagementAgreementsNetLeasePortfolioDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7687-bef5-18ef87a5c60a" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7687-bef5-18ef87a5c60a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_01a11c07-96fe-74a8-aae7-17cfd816371e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7687-bef5-18ef87a5c60a" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_01a11c07-96fe-74a8-aae7-17cfd816371e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a11c07-96fe-74a8-aae7-17cfd816371e_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_01a11c07-96fe-74a8-aae7-17cfd816371e" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a11c07-96fe-74a8-aae7-17cfd816371e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a11c07-96fe-7177-9bb0-9c6a11cbdf27" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_01a11c07-96fe-74a8-aae7-17cfd816371e" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a11c07-96fe-7177-9bb0-9c6a11cbdf27" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_01a11c07-96fe-7063-bddf-8d246e695358" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a11c07-96fe-7177-9bb0-9c6a11cbdf27" xlink:to="loc_svc_NetLeasePropertyMember_01a11c07-96fe-7063-bddf-8d246e695358" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_01a11c07-96fe-7fd5-8cfb-8067c53dab12" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_01a11c07-96fe-7fd5-8cfb-8067c53dab12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AreaOfRealEstateProperty_01a11c07-96fe-7a7c-8b0f-b08c7876f084" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AreaOfRealEstateProperty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_us-gaap_AreaOfRealEstateProperty_01a11c07-96fe-7a7c-8b0f-b08c7876f084" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementAnnualRentAndReturn_01a11c07-96fe-7d36-88c4-f69033d391be" xlink:href="svc-20260930.xsd#svc_OperatingAgreementAnnualRentAndReturn"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_svc_OperatingAgreementAnnualRentAndReturn_01a11c07-96fe-7d36-88c4-f69033d391be" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_01a11c07-96fe-72a3-a2a0-9d7e0f184aaa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_01a11c07-96fe-72a3-a2a0-9d7e0f184aaa" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PercentageOfPortfolioLeasedByTenants_01a11c07-96fe-7689-ba47-9adc935d98fe" xlink:href="svc-20260930.xsd#svc_PercentageOfPortfolioLeasedByTenants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_svc_PercentageOfPortfolioLeasedByTenants_01a11c07-96fe-7689-ba47-9adc935d98fe" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NumberOfTenants_01a11c07-96fe-71a7-b2cf-e66634516184" xlink:href="svc-20260930.xsd#svc_NumberOfTenants"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_svc_NumberOfTenants_01a11c07-96fe-71a7-b2cf-e66634516184" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AssetAcquisitionNumberOfBrands_01a11c07-96fe-7568-886b-53f23e14e844" xlink:href="svc-20260930.xsd#svc_AssetAcquisitionNumberOfBrands"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_svc_AssetAcquisitionNumberOfBrands_01a11c07-96fe-7568-886b-53f23e14e844" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AssetAcquisitionNumberOfIndustries_01a11c07-96fe-7f5d-b358-37846a12d5e8" xlink:href="svc-20260930.xsd#svc_AssetAcquisitionNumberOfIndustries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7b21-a967-52d2cbf65109" xlink:to="loc_svc_AssetAcquisitionNumberOfIndustries_01a11c07-96fe-7f5d-b358-37846a12d5e8" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/LeasesandManagementAgreementsTALeasesDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#LeasesandManagementAgreementsTALeasesDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/LeasesandManagementAgreementsTALeasesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7ca6-a73f-b5a6ec29ea2b" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7ca6-a73f-b5a6ec29ea2b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingLeasesOfLessorContractNameAxis_019fd756-d1be-71fe-9335-cdb1a8e0461a" xlink:href="svc-20260930.xsd#svc_OperatingLeasesOfLessorContractNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7ca6-a73f-b5a6ec29ea2b" xlink:to="loc_svc_OperatingLeasesOfLessorContractNameAxis_019fd756-d1be-71fe-9335-cdb1a8e0461a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingLeasesOfLessorContractNameDomain_019fd756-d1be-71fe-9335-cdb1a8e0461a_default" xlink:href="svc-20260930.xsd#svc_OperatingLeasesOfLessorContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_svc_OperatingLeasesOfLessorContractNameAxis_019fd756-d1be-71fe-9335-cdb1a8e0461a" xlink:to="loc_svc_OperatingLeasesOfLessorContractNameDomain_019fd756-d1be-71fe-9335-cdb1a8e0461a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingLeasesOfLessorContractNameDomain_019fd756-d1be-7eaf-a941-a682e0f5f2b3" xlink:href="svc-20260930.xsd#svc_OperatingLeasesOfLessorContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_svc_OperatingLeasesOfLessorContractNameAxis_019fd756-d1be-71fe-9335-cdb1a8e0461a" xlink:to="loc_svc_OperatingLeasesOfLessorContractNameDomain_019fd756-d1be-7eaf-a941-a682e0f5f2b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_TravelCentersOfAmericaMember_019fd756-d1be-7ed0-b85c-5a3a3d410bef" xlink:href="svc-20260930.xsd#svc_TravelCentersOfAmericaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_OperatingLeasesOfLessorContractNameDomain_019fd756-d1be-7eaf-a941-a682e0f5f2b3" xlink:to="loc_svc_TravelCentersOfAmericaMember_019fd756-d1be-7ed0-b85c-5a3a3d410bef" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7d89-80bb-a9befc79a381" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7ca6-a73f-b5a6ec29ea2b" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7d89-80bb-a9befc79a381" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7d89-80bb-a9befc79a381_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7d89-80bb-a9befc79a381" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7d89-80bb-a9befc79a381_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7b25-8f28-af62cea3ab17" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7d89-80bb-a9befc79a381" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7b25-8f28-af62cea3ab17" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_019fd756-d1be-73a1-aa13-aa81b8a365fd" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7b25-8f28-af62cea3ab17" xlink:to="loc_svc_NetLeasePropertyMember_019fd756-d1be-73a1-aa13-aa81b8a365fd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_TravelCentersMember_019fd756-d1be-7dce-9bcf-fe072e0f7654" xlink:href="svc-20260930.xsd#svc_TravelCentersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7b25-8f28-af62cea3ab17" xlink:to="loc_svc_TravelCentersMember_019fd756-d1be-7dce-9bcf-fe072e0f7654" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019fd756-d1be-76f5-b3aa-3a033e667738" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7ca6-a73f-b5a6ec29ea2b" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019fd756-d1be-76f5-b3aa-3a033e667738" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-76f5-b3aa-3a033e667738_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_019fd756-d1be-76f5-b3aa-3a033e667738" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-76f5-b3aa-3a033e667738_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-7194-af7d-470559476ca1" 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_019fd756-d1be-76f5-b3aa-3a033e667738" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-7194-af7d-470559476ca1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateInvestmentPropertyAtCostMember_019fd756-d1be-74c6-a99f-3116729b758c" xlink:href="svc-20260930.xsd#svc_RealEstateInvestmentPropertyAtCostMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-7194-af7d-470559476ca1" xlink:to="loc_svc_RealEstateInvestmentPropertyAtCostMember_019fd756-d1be-74c6-a99f-3116729b758c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019fd756-d1be-7c05-8e16-4b7682565f7b" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7ca6-a73f-b5a6ec29ea2b" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019fd756-d1be-7c05-8e16-4b7682565f7b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-7c05-8e16-4b7682565f7b_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_019fd756-d1be-7c05-8e16-4b7682565f7b" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-7c05-8e16-4b7682565f7b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-7678-a520-d1b89704cce1" 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_019fd756-d1be-7c05-8e16-4b7682565f7b" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-7678-a520-d1b89704cce1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditConcentrationRiskMember_019fd756-d1be-7f17-9a42-91fe372dcda7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-7678-a520-d1b89704cce1" xlink:to="loc_us-gaap_CreditConcentrationRiskMember_019fd756-d1be-7f17-9a42-91fe372dcda7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fd756-d1be-7678-b881-0dde7e36302e" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7ca6-a73f-b5a6ec29ea2b" xlink:to="loc_srt_CounterpartyNameAxis_019fd756-d1be-7678-b881-0dde7e36302e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7678-b881-0dde7e36302e_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_019fd756-d1be-7678-b881-0dde7e36302e" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7678-b881-0dde7e36302e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c76-ac95-3b3907ea188e" 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_019fd756-d1be-7678-b881-0dde7e36302e" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c76-ac95-3b3907ea188e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_TravelCentersOfAmericaIncMember_019fd756-d1be-74be-b9c1-26e6b7532a85" xlink:href="svc-20260930.xsd#svc_TravelCentersOfAmericaIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c76-ac95-3b3907ea188e" xlink:to="loc_svc_TravelCentersOfAmericaIncMember_019fd756-d1be-74be-b9c1-26e6b7532a85" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_BPProductsNorthAmericaIncMember_019fd756-d1be-7d57-9ab3-a41d015bbb22" xlink:href="svc-20260930.xsd#svc_BPProductsNorthAmericaIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7c76-ac95-3b3907ea188e" xlink:to="loc_svc_BPProductsNorthAmericaIncMember_019fd756-d1be-7d57-9ab3-a41d015bbb22" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7ff2-a372-1b81ea1abda6" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7ca6-a73f-b5a6ec29ea2b" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7ff2-a372-1b81ea1abda6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7ff2-a372-1b81ea1abda6_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_019fd756-d1be-7ff2-a372-1b81ea1abda6" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7ff2-a372-1b81ea1abda6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-71b2-bb2b-a47f5f0a0f5f" 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_019fd756-d1be-7ff2-a372-1b81ea1abda6" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-71b2-bb2b-a47f5f0a0f5f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019fd756-d1be-709d-9b2c-3e8a0877d5d0" 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_019fd756-d1be-71b2-bb2b-a47f5f0a0f5f" xlink:to="loc_us-gaap_RelatedPartyMember_019fd756-d1be-709d-9b2c-3e8a0877d5d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019fd756-d1be-7c14-a9fa-7397590ad5c9" 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_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019fd756-d1be-7c14-a9fa-7397590ad5c9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-78b4-95e0-e7ec83545766" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-78b4-95e0-e7ec83545766" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_LessorOperatingLeaseNumberOfRenewalOptions_019fd756-d1be-719c-b9e2-a26493b63948" xlink:href="svc-20260930.xsd#svc_LessorOperatingLeaseNumberOfRenewalOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_svc_LessorOperatingLeaseNumberOfRenewalOptions_019fd756-d1be-719c-b9e2-a26493b63948" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementAnnualRentAndReturn_019fd756-d1be-7005-bf9e-18885ca927f8" xlink:href="svc-20260930.xsd#svc_OperatingAgreementAnnualRentAndReturn"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_svc_OperatingAgreementAnnualRentAndReturn_019fd756-d1be-7005-bf9e-18885ca927f8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingLeasesMonthlyRentCredit_019fd756-d1be-7b25-ab26-ceed997f5550" xlink:href="svc-20260930.xsd#svc_OperatingLeasesMonthlyRentCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_svc_OperatingLeasesMonthlyRentCredit_019fd756-d1be-7b25-ab26-ceed997f5550" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseTermOfContract_019fd756-d1be-7da8-81eb-cb663c72f475" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseTermOfContract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_us-gaap_LesseeOperatingLeaseTermOfContract_019fd756-d1be-7da8-81eb-cb663c72f475" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GuaranteeObligationsMaximumExposure_019fd756-d1be-7651-a327-92c6e7878353" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsMaximumExposure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_us-gaap_GuaranteeObligationsMaximumExposure_019fd756-d1be-7651-a327-92c6e7878353" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLeaseIncomeLeasePayments_019fd756-d1be-7897-9da2-403fd3164927" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLeaseIncomeLeasePayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_us-gaap_OperatingLeaseLeaseIncomeLeasePayments_019fd756-d1be-7897-9da2-403fd3164927" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StraightLineRentAdjustments_019fd756-d1be-7369-803e-71b9eabd1ba4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StraightLineRentAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_us-gaap_StraightLineRentAdjustments_019fd756-d1be-7369-803e-71b9eabd1ba4" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionsAccrualsForUnpaidRentIncludingDeferredRent_019fd756-d1be-75cc-a0e9-70bcb15dd60d" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionsAccrualsForUnpaidRentIncludingDeferredRent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7d5f-a538-e70f5a540978" xlink:to="loc_svc_RelatedPartyTransactionsAccrualsForUnpaidRentIncludingDeferredRent_019fd756-d1be-75cc-a0e9-70bcb15dd60d" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/LeasesandManagementAgreementsOtherNetLeasePropertiesDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#LeasesandManagementAgreementsOtherNetLeasePropertiesDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/LeasesandManagementAgreementsOtherNetLeasePropertiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7fd4-b36a-e1c6fb02c1ab" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a65-af3a-f3fd1c9537a7" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7fd4-b36a-e1c6fb02c1ab" xlink:to="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a65-af3a-f3fd1c9537a7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameAxis_01a11c0b-ed37-7666-8a21-59c2ebf50c6a" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a65-af3a-f3fd1c9537a7" xlink:to="loc_svc_ManagementAgreementContractNameAxis_01a11c0b-ed37-7666-8a21-59c2ebf50c6a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_01a11c0b-ed37-7666-8a21-59c2ebf50c6a_default" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_svc_ManagementAgreementContractNameAxis_01a11c0b-ed37-7666-8a21-59c2ebf50c6a" xlink:to="loc_svc_ManagementAgreementContractNameDomain_01a11c0b-ed37-7666-8a21-59c2ebf50c6a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_01a11c0b-ed37-7e29-b20e-4f04eb2ef512" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_svc_ManagementAgreementContractNameAxis_01a11c0b-ed37-7666-8a21-59c2ebf50c6a" xlink:to="loc_svc_ManagementAgreementContractNameDomain_01a11c0b-ed37-7e29-b20e-4f04eb2ef512" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SpiritMTAREITTransactionMember_01a11c0b-ed37-71dc-af24-aaea199187ea" xlink:href="svc-20260930.xsd#svc_SpiritMTAREITTransactionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementContractNameDomain_01a11c0b-ed37-7e29-b20e-4f04eb2ef512" xlink:to="loc_svc_SpiritMTAREITTransactionMember_01a11c0b-ed37-71dc-af24-aaea199187ea" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnusualOrInfrequentItemAxis_01a11c0b-ed37-78f0-ad9a-68435c1d96a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnusualOrInfrequentItemAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a65-af3a-f3fd1c9537a7" xlink:to="loc_us-gaap_UnusualOrInfrequentItemAxis_01a11c0b-ed37-78f0-ad9a-68435c1d96a5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnusualOrInfrequentItemDomain_01a11c0b-ed37-78f0-ad9a-68435c1d96a5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnusualOrInfrequentItemDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_UnusualOrInfrequentItemAxis_01a11c0b-ed37-78f0-ad9a-68435c1d96a5" xlink:to="loc_us-gaap_UnusualOrInfrequentItemDomain_01a11c0b-ed37-78f0-ad9a-68435c1d96a5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnusualOrInfrequentItemDomain_01a11c0b-ed37-797a-822b-f9fa80736db5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnusualOrInfrequentItemDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_UnusualOrInfrequentItemAxis_01a11c0b-ed37-78f0-ad9a-68435c1d96a5" xlink:to="loc_us-gaap_UnusualOrInfrequentItemDomain_01a11c0b-ed37-797a-822b-f9fa80736db5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_COVID19Member_01a11c0b-ed37-77d8-9775-fa9b22d05e40" xlink:href="svc-20260930.xsd#svc_COVID19Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_UnusualOrInfrequentItemDomain_01a11c0b-ed37-797a-822b-f9fa80736db5" xlink:to="loc_svc_COVID19Member_01a11c0b-ed37-77d8-9775-fa9b22d05e40" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLeaseIncomeLeasePayments_01a11c0b-ed37-761d-abc5-8fa88f0940bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLeaseIncomeLeasePayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7fd4-b36a-e1c6fb02c1ab" xlink:to="loc_us-gaap_OperatingLeaseLeaseIncomeLeasePayments_01a11c0b-ed37-761d-abc5-8fa88f0940bb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StraightLineRentAdjustments_01a11c0b-ed37-756a-871e-7d9c9a9aa648" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StraightLineRentAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7fd4-b36a-e1c6fb02c1ab" xlink:to="loc_us-gaap_StraightLineRentAdjustments_01a11c0b-ed37-756a-871e-7d9c9a9aa648" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease_01a11c0b-ed37-7814-a7cf-27df1cf3939d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7fd4-b36a-e1c6fb02c1ab" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease_01a11c0b-ed37-7814-a7cf-27df1cf3939d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_01a11c0b-ed37-779b-a231-43aa513ba68e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7fd4-b36a-e1c6fb02c1ab" xlink:to="loc_us-gaap_AllowanceForDoubtfulAccountsReceivable_01a11c0b-ed37-779b-a231-43aa513ba68e" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/LeasesandManagementAgreementsSonestaAgreementDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#LeasesandManagementAgreementsSonestaAgreementDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/LeasesandManagementAgreementsSonestaAgreementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fd756-d1be-72a7-b269-e4dba2973889" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_srt_CounterpartyNameAxis_019fd756-d1be-72a7-b269-e4dba2973889" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-72a7-b269-e4dba2973889_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_019fd756-d1be-72a7-b269-e4dba2973889" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-72a7-b269-e4dba2973889_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7f14-bc10-45a4a4313b90" 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_019fd756-d1be-72a7-b269-e4dba2973889" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7f14-bc10-45a4a4313b90" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d1be-77f7-a134-4a580774d1d5" xlink:href="svc-20260930.xsd#svc_SonestaInternationalHotelsCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7f14-bc10-45a4a4313b90" xlink:to="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d1be-77f7-a134-4a580774d1d5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7514-be59-d7648102ab15" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7514-be59-d7648102ab15" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7514-be59-d7648102ab15_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7514-be59-d7648102ab15" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7514-be59-d7648102ab15_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7ecb-97c1-ae97e07f00f8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7514-be59-d7648102ab15" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7ecb-97c1-ae97e07f00f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-7f6a-bdb1-9e567aa5ed93" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7ecb-97c1-ae97e07f00f8" xlink:to="loc_srt_HotelMember_019fd756-d1be-7f6a-bdb1-9e567aa5ed93" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019fd756-d1be-77ae-b96e-1f3323df5589" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_srt_ProductOrServiceAxis_019fd756-d1be-77ae-b96e-1f3323df5589" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019fd756-d1be-77ae-b96e-1f3323df5589_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019fd756-d1be-77ae-b96e-1f3323df5589" xlink:to="loc_srt_ProductsAndServicesDomain_019fd756-d1be-77ae-b96e-1f3323df5589_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019fd756-d1be-70cb-a25a-775809d17439" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019fd756-d1be-77ae-b96e-1f3323df5589" xlink:to="loc_srt_ProductsAndServicesDomain_019fd756-d1be-70cb-a25a-775809d17439" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_FullServiceHotelMember_019fd756-d1be-72ec-9375-a76417f57d97" xlink:href="svc-20260930.xsd#svc_FullServiceHotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019fd756-d1be-70cb-a25a-775809d17439" xlink:to="loc_svc_FullServiceHotelMember_019fd756-d1be-72ec-9375-a76417f57d97" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_LimitedServicesHotelMember_019fd756-d1be-7402-be98-15b42dedb072" xlink:href="svc-20260930.xsd#svc_LimitedServicesHotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019fd756-d1be-70cb-a25a-775809d17439" xlink:to="loc_svc_LimitedServicesHotelMember_019fd756-d1be-7402-be98-15b42dedb072" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SelectServiceHotelsMember_019fd756-d1be-76c2-b1fd-77732946df00" xlink:href="svc-20260930.xsd#svc_SelectServiceHotelsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019fd756-d1be-70cb-a25a-775809d17439" xlink:to="loc_svc_SelectServiceHotelsMember_019fd756-d1be-76c2-b1fd-77732946df00" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019fd756-d1be-771c-9a5c-f14a4b0def57" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_019fd756-d1be-771c-9a5c-f14a4b0def57" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-771c-9a5c-f14a4b0def57_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_019fd756-d1be-771c-9a5c-f14a4b0def57" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-771c-9a5c-f14a4b0def57_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-70ac-83f1-35855f4c7a4f" 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_019fd756-d1be-771c-9a5c-f14a4b0def57" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-70ac-83f1-35855f4c7a4f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateInvestmentPropertyAtCostMember_019fd756-d1be-70ec-ab91-6132352dfb39" xlink:href="svc-20260930.xsd#svc_RealEstateInvestmentPropertyAtCostMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_019fd756-d1be-70ac-83f1-35855f4c7a4f" xlink:to="loc_svc_RealEstateInvestmentPropertyAtCostMember_019fd756-d1be-70ec-ab91-6132352dfb39" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_019fd756-d1be-733e-b4a8-d2651d23093a" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_019fd756-d1be-733e-b4a8-d2651d23093a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-733e-b4a8-d2651d23093a_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_019fd756-d1be-733e-b4a8-d2651d23093a" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-733e-b4a8-d2651d23093a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-7f05-b59d-734f82fd7b16" 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_019fd756-d1be-733e-b4a8-d2651d23093a" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-7f05-b59d-734f82fd7b16" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditConcentrationRiskMember_019fd756-d1be-7919-b9ab-b3b87023d9a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_019fd756-d1be-7f05-b59d-734f82fd7b16" xlink:to="loc_us-gaap_CreditConcentrationRiskMember_019fd756-d1be-7919-b9ab-b3b87023d9a2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-78ed-8730-15865219649f" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-78ed-8730-15865219649f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-78ed-8730-15865219649f_default" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-78ed-8730-15865219649f" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-78ed-8730-15865219649f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7c4c-8727-fc4322d12296" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-78ed-8730-15865219649f" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7c4c-8727-fc4322d12296" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SonestaAgreementMember_019fd756-d1be-7ca5-b3f7-b6a8eab31fe8" xlink:href="svc-20260930.xsd#svc_SonestaAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7c4c-8727-fc4322d12296" xlink:to="loc_svc_SonestaAgreementMember_019fd756-d1be-7ca5-b3f7-b6a8eab31fe8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-7d7f-9a32-ac84098223e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-7d7f-9a32-ac84098223e3" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7d7f-9a32-ac84098223e3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-7d7f-9a32-ac84098223e3" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7d7f-9a32-ac84098223e3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7e64-a454-d92e0e172847" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d1be-7d7f-9a32-ac84098223e3" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7e64-a454-d92e0e172847" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_019fd756-d1be-7280-aa42-2af96c4d355c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7e64-a454-d92e0e172847" xlink:to="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_019fd756-d1be-7280-aa42-2af96c4d355c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_01a15e71-7f4f-716e-b3f2-d6f3bf17691e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d1be-7e64-a454-d92e0e172847" xlink:to="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_01a15e71-7f4f-716e-b3f2-d6f3bf17691e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-79cb-b16e-fe11c1d0aa41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-79cb-b16e-fe11c1d0aa41" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-79cb-b16e-fe11c1d0aa41_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-79cb-b16e-fe11c1d0aa41" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-79cb-b16e-fe11c1d0aa41_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-7417-8745-d4d70512c130" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d1be-79cb-b16e-fe11c1d0aa41" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-7417-8745-d4d70512c130" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateDispositionsMember_019fd756-d1be-77c2-84d4-0f3013ff2904" xlink:href="svc-20260930.xsd#svc_RealEstateDispositionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d1be-7417-8745-d4d70512c130" xlink:to="loc_svc_RealEstateDispositionsMember_019fd756-d1be-77c2-84d4-0f3013ff2904" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_019fd756-d1be-7534-a3ab-16ce980dad3e" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_019fd756-d1be-7534-a3ab-16ce980dad3e" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d1be-7534-a3ab-16ce980dad3e_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_019fd756-d1be-7534-a3ab-16ce980dad3e" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d1be-7534-a3ab-16ce980dad3e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d1be-7d1f-af5a-c7c0040aadb7" 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_019fd756-d1be-7534-a3ab-16ce980dad3e" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d1be-7d1f-af5a-c7c0040aadb7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ReturnOfCapitalMember_019fd756-d1be-735f-82fb-82e07f677ef9" xlink:href="svc-20260930.xsd#svc_ReturnOfCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d1be-7d1f-af5a-c7c0040aadb7" xlink:to="loc_svc_ReturnOfCapitalMember_019fd756-d1be-735f-82fb-82e07f677ef9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_019fd756-d1be-7607-a23d-dbd3599a3fd8" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-77e8-83fc-5aa14d9d0629" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_019fd756-d1be-7607-a23d-dbd3599a3fd8" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-7607-a23d-dbd3599a3fd8_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_019fd756-d1be-7607-a23d-dbd3599a3fd8" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-7607-a23d-dbd3599a3fd8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-7a9b-8bad-34e9e6d67ebb" 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_019fd756-d1be-7607-a23d-dbd3599a3fd8" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-7a9b-8bad-34e9e6d67ebb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_019fd756-d1be-703c-b890-a0a5d110280b" 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_019fd756-d1be-7a9b-8bad-34e9e6d67ebb" xlink:to="loc_us-gaap_SubsequentEventMember_019fd756-d1be-703c-b890-a0a5d110280b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HotelManagementAgreementsAndLeasesRealEstatePropertiesUnderAgreement_019fd756-d1be-713b-a289-413e9fc06d99" xlink:href="svc-20260930.xsd#svc_HotelManagementAgreementsAndLeasesRealEstatePropertiesUnderAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_HotelManagementAgreementsAndLeasesRealEstatePropertiesUnderAgreement_019fd756-d1be-713b-a289-413e9fc06d99" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_019fd756-d1be-74a9-add2-2d98fd169161" 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_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_019fd756-d1be-74a9-add2-2d98fd169161" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-72c0-ab69-06102b653c9a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-72c0-ab69-06102b653c9a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfUnitsInRealEstateProperty_019fd756-d1be-7d44-b354-142d78ae407b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfUnitsInRealEstateProperty"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_us-gaap_NumberOfUnitsInRealEstateProperty_019fd756-d1be-7d44-b354-142d78ae407b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PercentPaymentOfHotelCashFlows_019fd756-d1be-75ef-9b70-72c6d9a12598" xlink:href="svc-20260930.xsd#svc_PercentPaymentOfHotelCashFlows"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_PercentPaymentOfHotelCashFlows_019fd756-d1be-75ef-9b70-72c6d9a12598" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementsNumberOfRenewalOptions_019fd756-d1be-77e7-99f1-866c663d84af" xlink:href="svc-20260930.xsd#svc_OperatingAgreementsNumberOfRenewalOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_OperatingAgreementsNumberOfRenewalOptions_019fd756-d1be-77e7-99f1-866c663d84af" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementsTermOfRenewalOptions_019fd756-d1be-77aa-b43e-204d481246b4" xlink:href="svc-20260930.xsd#svc_OperatingAgreementsTermOfRenewalOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_OperatingAgreementsTermOfRenewalOptions_019fd756-d1be-77aa-b43e-204d481246b4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionBaseManagementFeePercentOfGrossRevenues_019fd756-d1be-70aa-b483-070dc353afda" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionBaseManagementFeePercentOfGrossRevenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionBaseManagementFeePercentOfGrossRevenues_019fd756-d1be-70aa-b483-070dc353afda" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionIncentiveFeePercentOfEBITDA_019fd756-d1be-7b4c-a5cd-19c85a35db7e" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionIncentiveFeePercentOfEBITDA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionIncentiveFeePercentOfEBITDA_019fd756-d1be-7b4c-a5cd-19c85a35db7e" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_019fd756-d1be-7947-b2e6-0c8ee0c1fd8f" 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_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_019fd756-d1be-7947-b2e6-0c8ee0c1fd8f" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AnnualOwnersReturnAmountEqualsToIncentiveThreshold_019fd756-d1be-7c40-8250-00cede53da08" xlink:href="svc-20260930.xsd#svc_AnnualOwnersReturnAmountEqualsToIncentiveThreshold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_AnnualOwnersReturnAmountEqualsToIncentiveThreshold_019fd756-d1be-7c40-8250-00cede53da08" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionBrandPromotionFeePercentOfGrossRoomRevenues_019fd756-d1be-7425-837a-573cb760c095" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionBrandPromotionFeePercentOfGrossRoomRevenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionBrandPromotionFeePercentOfGrossRoomRevenues_019fd756-d1be-7425-837a-573cb760c095" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionsLoyaltyFeePercentOfGrossRoomRevenues_019fd756-d1be-703a-9060-1741ecff6adc" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionsLoyaltyFeePercentOfGrossRoomRevenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionsLoyaltyFeePercentOfGrossRoomRevenues_019fd756-d1be-703a-9060-1741ecff6adc" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionLoyaltyFeePercentOfQualifiedRoomRevenues_019fd756-d1be-7f32-9689-225d65c327ca" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionLoyaltyFeePercentOfQualifiedRoomRevenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionLoyaltyFeePercentOfQualifiedRoomRevenues_019fd756-d1be-7f32-9689-225d65c327ca" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionCentralizedServiceFee_019fd756-d1be-74a1-b786-26d663696a3c" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionCentralizedServiceFee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionCentralizedServiceFee_019fd756-d1be-74a1-b786-26d663696a3c" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionConstructionManagementFeePercentage_019fd756-d1be-72ff-b9cc-0adabf0725a9" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionConstructionManagementFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionConstructionManagementFeePercentage_019fd756-d1be-72ff-b9cc-0adabf0725a9" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionTerminationPerformanceThresholdPeriod_019fd756-d1be-7e1d-aadc-707414854ca3" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionTerminationPerformanceThresholdPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionTerminationPerformanceThresholdPeriod_019fd756-d1be-7e1d-aadc-707414854ca3" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HotelManagementAgreementTerminationFee_01a17ecf-29bc-78de-a09e-f71a2f4666fa" xlink:href="svc-20260930.xsd#svc_HotelManagementAgreementTerminationFee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_HotelManagementAgreementTerminationFee_01a17ecf-29bc-78de-a09e-f71a2f4666fa" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HotelManagementAgreementIncomeLoss_019fd756-d1be-78d2-8dfc-b9c6ff89d8a7" xlink:href="svc-20260930.xsd#svc_HotelManagementAgreementIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_HotelManagementAgreementIncomeLoss_019fd756-d1be-78d2-8dfc-b9c6ff89d8a7" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionVariousManagementOperatingFees_019fd756-d1be-7b39-97c0-0f2021f400ea" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionVariousManagementOperatingFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionVariousManagementOperatingFees_019fd756-d1be-7b39-97c0-0f2021f400ea" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AccruedIncentiveFee_019fd756-d1be-7a0a-a71d-d7c29cc7f256" xlink:href="svc-20260930.xsd#svc_AccruedIncentiveFee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_AccruedIncentiveFee_019fd756-d1be-7a0a-a71d-d7c29cc7f256" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionProcurementAndConstructionSupervisoryFees_019fd756-d1be-7645-8582-347fd0833a85" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionProcurementAndConstructionSupervisoryFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_RelatedPartyTransactionProcurementAndConstructionSupervisoryFees_019fd756-d1be-7645-8582-347fd0833a85" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-7876-b627-5e0b4989795c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForCapitalImprovements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-7876-b627-5e0b4989795c" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DueToRelatedPartyReimbursementOfCapitalExpendituresAndOther_019fd756-d1be-7f9c-b58f-999764c9d179" xlink:href="svc-20260930.xsd#svc_DueToRelatedPartyReimbursementOfCapitalExpendituresAndOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_DueToRelatedPartyReimbursementOfCapitalExpendituresAndOther_019fd756-d1be-7f9c-b58f-999764c9d179" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherReceivables_019fd756-d1be-724d-a3ed-78892607edb1" 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_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_us-gaap_OtherReceivables_019fd756-d1be-724d-a3ed-78892607edb1" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PercentOfGrossRevenuesFromHotelOperationsPlacedIntoEscrowOrFurnitureFixturesAndEquipmentReserve_019fd756-d1be-7b50-946d-264aebca9b64" xlink:href="svc-20260930.xsd#svc_PercentOfGrossRevenuesFromHotelOperationsPlacedIntoEscrowOrFurnitureFixturesAndEquipmentReserve"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_PercentOfGrossRevenuesFromHotelOperationsPlacedIntoEscrowOrFurnitureFixturesAndEquipmentReserve_019fd756-d1be-7b50-946d-264aebca9b64" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EscrowDepositsRelatedToPropertySales_019fd756-d1be-7d49-bffc-8664db1895b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EscrowDepositsRelatedToPropertySales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_us-gaap_EscrowDepositsRelatedToPropertySales_019fd756-d1be-7d49-bffc-8664db1895b9" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_LessorOperatingLeasesAdvancedWorkingCapital_019fd756-d1be-72f7-8454-a0dcacdc23a8" xlink:href="svc-20260930.xsd#svc_LessorOperatingLeasesAdvancedWorkingCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7160-b3e3-715dac84d882" xlink:to="loc_svc_LessorOperatingLeasesAdvancedWorkingCapital_019fd756-d1be-72f7-8454-a0dcacdc23a8" xlink:type="arc" order="27"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/LeasesandManagementAgreementsHyattAgreementDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#LeasesandManagementAgreementsHyattAgreementDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/LeasesandManagementAgreementsHyattAgreementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a4b-8112-f20d5db3f505" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a4b-8112-f20d5db3f505" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fd756-d1be-7e3a-a9cb-bf3c348e801f" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a4b-8112-f20d5db3f505" xlink:to="loc_srt_CounterpartyNameAxis_019fd756-d1be-7e3a-a9cb-bf3c348e801f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7e3a-a9cb-bf3c348e801f_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_019fd756-d1be-7e3a-a9cb-bf3c348e801f" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7e3a-a9cb-bf3c348e801f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7827-956b-ade0e50df999" 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_019fd756-d1be-7e3a-a9cb-bf3c348e801f" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7827-956b-ade0e50df999" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HyattHotelsCorporationMember_019fd756-d1be-7fb3-bf62-bc4dded38535" xlink:href="svc-20260930.xsd#svc_HyattHotelsCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7827-956b-ade0e50df999" xlink:to="loc_svc_HyattHotelsCorporationMember_019fd756-d1be-7fb3-bf62-bc4dded38535" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7930-8831-1fcd948dc6c5" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a4b-8112-f20d5db3f505" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7930-8831-1fcd948dc6c5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7930-8831-1fcd948dc6c5_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7930-8831-1fcd948dc6c5" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7930-8831-1fcd948dc6c5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7ff7-bcc7-2d6963bfa489" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7930-8831-1fcd948dc6c5" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7ff7-bcc7-2d6963bfa489" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-7fe0-98d3-78789d09c14d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7ff7-bcc7-2d6963bfa489" xlink:to="loc_srt_HotelMember_019fd756-d1be-7fe0-98d3-78789d09c14d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-773d-a78d-4fb307775644" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a4b-8112-f20d5db3f505" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-773d-a78d-4fb307775644" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-773d-a78d-4fb307775644_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_019fd756-d1be-773d-a78d-4fb307775644" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-773d-a78d-4fb307775644_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7f17-8ecf-f7f2cfa3e13e" 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_019fd756-d1be-773d-a78d-4fb307775644" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7f17-8ecf-f7f2cfa3e13e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019fd756-d1be-7256-ac1c-07cbbf1a8f8d" 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_019fd756-d1be-7f17-8ecf-f7f2cfa3e13e" xlink:to="loc_us-gaap_RelatedPartyMember_019fd756-d1be-7256-ac1c-07cbbf1a8f8d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-76b0-9cc8-821103a51053" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7a4b-8112-f20d5db3f505" xlink:to="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-76b0-9cc8-821103a51053" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-76b0-9cc8-821103a51053_default" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-76b0-9cc8-821103a51053" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-76b0-9cc8-821103a51053_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-78a3-bf38-9edecf65e574" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-76b0-9cc8-821103a51053" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-78a3-bf38-9edecf65e574" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HyattHotelsCorporationContractMember_019fd756-d1be-7f8d-9b1f-13485fdb1bf0" xlink:href="svc-20260930.xsd#svc_HyattHotelsCorporationContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-78a3-bf38-9edecf65e574" xlink:to="loc_svc_HyattHotelsCorporationContractMember_019fd756-d1be-7f8d-9b1f-13485fdb1bf0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-79ba-9cf3-a5c837018a4d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-79ba-9cf3-a5c837018a4d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementAnnualRentAndReturn_019fd756-d1be-7ba0-94a5-d3f1fdd4ce42" xlink:href="svc-20260930.xsd#svc_OperatingAgreementAnnualRentAndReturn"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_svc_OperatingAgreementAnnualRentAndReturn_019fd756-d1be-7ba0-94a5-d3f1fdd4ce42" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementLimitedGuarantee_019fd756-d1be-715a-b408-ea1ab8e3dfa2" xlink:href="svc-20260930.xsd#svc_OperatingAgreementLimitedGuarantee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_svc_OperatingAgreementLimitedGuarantee_019fd756-d1be-715a-b408-ea1ab8e3dfa2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementLimitedGuaranteePercentageOfAnnualMinimumReturns_019fd756-d1be-7268-8e2b-2546a8e80581" xlink:href="svc-20260930.xsd#svc_OperatingAgreementLimitedGuaranteePercentageOfAnnualMinimumReturns"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_svc_OperatingAgreementLimitedGuaranteePercentageOfAnnualMinimumReturns_019fd756-d1be-7268-8e2b-2546a8e80581" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HotelManagementAgreementRealizedIncomeLoss_019fd756-d1be-7137-b7a7-c205344dc88b" xlink:href="svc-20260930.xsd#svc_HotelManagementAgreementRealizedIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_svc_HotelManagementAgreementRealizedIncomeLoss_019fd756-d1be-7137-b7a7-c205344dc88b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PropertyAgreementGuaranteePaymentToCoverShortfall_019fd756-d1be-722a-8af5-c592016cf79a" xlink:href="svc-20260930.xsd#svc_PropertyAgreementGuaranteePaymentToCoverShortfall"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_svc_PropertyAgreementGuaranteePaymentToCoverShortfall_019fd756-d1be-722a-8af5-c592016cf79a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PropertyAgreementGuaranteeReceivedByEntityAmount_019fd756-d1be-7023-b340-2507b177af7a" xlink:href="svc-20260930.xsd#svc_PropertyAgreementGuaranteeReceivedByEntityAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_svc_PropertyAgreementGuaranteeReceivedByEntityAmount_019fd756-d1be-7023-b340-2507b177af7a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-7bc1-b534-0981f74dfcb3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForCapitalImprovements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7305-8512-55d45e419a55" xlink:to="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-7bc1-b534-0981f74dfcb3" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/LeasesandManagementAgreementsRadissonAgreementDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#LeasesandManagementAgreementsRadissonAgreementDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/LeasesandManagementAgreementsRadissonAgreementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-70f7-a779-f7dccd8c0eec" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-70f7-a779-f7dccd8c0eec" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fd756-d1be-7eb7-96e1-bc0f03cd8eb2" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-70f7-a779-f7dccd8c0eec" xlink:to="loc_srt_CounterpartyNameAxis_019fd756-d1be-7eb7-96e1-bc0f03cd8eb2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7eb7-96e1-bc0f03cd8eb2_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_019fd756-d1be-7eb7-96e1-bc0f03cd8eb2" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7eb7-96e1-bc0f03cd8eb2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7d95-a8d0-982adc0a0e06" 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_019fd756-d1be-7eb7-96e1-bc0f03cd8eb2" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7d95-a8d0-982adc0a0e06" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RadissonHospitalityIncMember_019fd756-d1be-788a-a0fb-4e869a971425" xlink:href="svc-20260930.xsd#svc_RadissonHospitalityIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d1be-7d95-a8d0-982adc0a0e06" xlink:to="loc_svc_RadissonHospitalityIncMember_019fd756-d1be-788a-a0fb-4e869a971425" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7ec6-b895-5a8d40f096c6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-70f7-a779-f7dccd8c0eec" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7ec6-b895-5a8d40f096c6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7ec6-b895-5a8d40f096c6_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7ec6-b895-5a8d40f096c6" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7ec6-b895-5a8d40f096c6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-77f2-8ac4-00955187e413" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7ec6-b895-5a8d40f096c6" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-77f2-8ac4-00955187e413" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-7923-8a71-a5bb3b269ac6" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-77f2-8ac4-00955187e413" xlink:to="loc_srt_HotelMember_019fd756-d1be-7923-8a71-a5bb3b269ac6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7a80-a7c0-20ad855aa887" 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_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-70f7-a779-f7dccd8c0eec" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d1be-7a80-a7c0-20ad855aa887" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7a80-a7c0-20ad855aa887_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_019fd756-d1be-7a80-a7c0-20ad855aa887" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-7a80-a7c0-20ad855aa887_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-758c-8e87-bbe141a321f2" 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_019fd756-d1be-7a80-a7c0-20ad855aa887" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d1be-758c-8e87-bbe141a321f2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019fd756-d1be-7b08-88c3-1aa7f585f1a9" 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_019fd756-d1be-758c-8e87-bbe141a321f2" xlink:to="loc_us-gaap_RelatedPartyMember_019fd756-d1be-7b08-88c3-1aa7f585f1a9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7c72-a715-4f78853e671e" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-70f7-a779-f7dccd8c0eec" xlink:to="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7c72-a715-4f78853e671e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7c72-a715-4f78853e671e_default" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7c72-a715-4f78853e671e" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7c72-a715-4f78853e671e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-73b2-8c65-f60bfb37ddec" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7c72-a715-4f78853e671e" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-73b2-8c65-f60bfb37ddec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RadissonAgreementMember_019fd756-d1be-7210-8011-214bd616fb95" xlink:href="svc-20260930.xsd#svc_RadissonAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-73b2-8c65-f60bfb37ddec" xlink:to="loc_svc_RadissonAgreementMember_019fd756-d1be-7210-8011-214bd616fb95" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-785e-bb9c-cac034213d20" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-785e-bb9c-cac034213d20" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementAnnualRentAndReturn_019fd756-d1be-7a5f-9544-c4ada8f12dba" xlink:href="svc-20260930.xsd#svc_OperatingAgreementAnnualRentAndReturn"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_svc_OperatingAgreementAnnualRentAndReturn_019fd756-d1be-7a5f-9544-c4ada8f12dba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementLimitedGuarantee_019fd756-d1be-70b5-ac4e-a05a59f5156c" xlink:href="svc-20260930.xsd#svc_OperatingAgreementLimitedGuarantee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_svc_OperatingAgreementLimitedGuarantee_019fd756-d1be-70b5-ac4e-a05a59f5156c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementLimitedGuaranteePercentageOfAnnualMinimumReturns_019fd756-d1be-7d36-abd3-d83d162b469f" xlink:href="svc-20260930.xsd#svc_OperatingAgreementLimitedGuaranteePercentageOfAnnualMinimumReturns"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_svc_OperatingAgreementLimitedGuaranteePercentageOfAnnualMinimumReturns_019fd756-d1be-7d36-abd3-d83d162b469f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HotelManagementAgreementRealizedIncomeLoss_019fd756-d1be-76f2-bb20-20838dc825ef" xlink:href="svc-20260930.xsd#svc_HotelManagementAgreementRealizedIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_svc_HotelManagementAgreementRealizedIncomeLoss_019fd756-d1be-76f2-bb20-20838dc825ef" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PropertyAgreementGuaranteePaymentToCoverShortfall_019fd756-d1be-766e-b9d0-5b93f13fab1d" xlink:href="svc-20260930.xsd#svc_PropertyAgreementGuaranteePaymentToCoverShortfall"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_svc_PropertyAgreementGuaranteePaymentToCoverShortfall_019fd756-d1be-766e-b9d0-5b93f13fab1d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PropertyAgreementGuaranteeReceivedByEntityAmount_019fd756-d1be-7cc5-8458-bdc7a69965ec" xlink:href="svc-20260930.xsd#svc_PropertyAgreementGuaranteeReceivedByEntityAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_svc_PropertyAgreementGuaranteeReceivedByEntityAmount_019fd756-d1be-7cc5-8458-bdc7a69965ec" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-7563-ac6b-4bf26b5e9721" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForCapitalImprovements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-7563-ac6b-4bf26b5e9721" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementIncreaseDecreaseInAnnualRentAndReturn_019fd756-d1be-717b-b055-6c98f99f5a4f" xlink:href="svc-20260930.xsd#svc_OperatingAgreementIncreaseDecreaseInAnnualRentAndReturn"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-7721-9a11-f810d7cb5d01" xlink:to="loc_svc_OperatingAgreementIncreaseDecreaseInAnnualRentAndReturn_019fd756-d1be-717b-b055-6c98f99f5a4f" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/LeasesandManagementAgreementsIHGAgreementDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#LeasesandManagementAgreementsIHGAgreementDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/LeasesandManagementAgreementsIHGAgreementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-752c-b93e-50a445f209ad" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7c23-a909-ab5b7dc5e721" xlink:href="svc-20260930.xsd#svc_ManagementAgreementsAndLeasesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-752c-b93e-50a445f209ad" xlink:to="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7c23-a909-ab5b7dc5e721" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7e5a-9682-c4af92038d89" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7c23-a909-ab5b7dc5e721" xlink:to="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7e5a-9682-c4af92038d89" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7e5a-9682-c4af92038d89_default" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7e5a-9682-c4af92038d89" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7e5a-9682-c4af92038d89_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7aff-b58e-ab99fdf63bf2" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-7e5a-9682-c4af92038d89" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7aff-b58e-ab99fdf63bf2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_IHGAgreementMember_019fd756-d1be-7c27-ad2c-8d7ea1286072" xlink:href="svc-20260930.xsd#svc_IHGAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-7aff-b58e-ab99fdf63bf2" xlink:to="loc_svc_IHGAgreementMember_019fd756-d1be-7c27-ad2c-8d7ea1286072" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7092-99d4-e0539094c13b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_svc_ManagementAgreementsAndLeasesTable_019fd756-d1be-7c23-a909-ab5b7dc5e721" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7092-99d4-e0539094c13b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7092-99d4-e0539094c13b_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7092-99d4-e0539094c13b" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7092-99d4-e0539094c13b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7fb6-a55e-0eabc0254ef4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d1be-7092-99d4-e0539094c13b" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7fb6-a55e-0eabc0254ef4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d1be-7571-93aa-712151665e34" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d1be-7fb6-a55e-0eabc0254ef4" xlink:to="loc_srt_HotelMember_019fd756-d1be-7571-93aa-712151665e34" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7e10-ac37-6960c940293e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-752c-b93e-50a445f209ad" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d1be-7e10-ac37-6960c940293e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fd756-d1be-7cc9-83f2-1c4a8798ed64" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-752c-b93e-50a445f209ad" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_019fd756-d1be-7cc9-83f2-1c4a8798ed64" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-727a-94ac-961a7442236b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForCapitalImprovements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementsAndLeasesLineItems_019fd756-d1be-752c-b93e-50a445f209ad" xlink:to="loc_us-gaap_PaymentsForCapitalImprovements_019fd756-d1be-727a-94ac-961a7442236b" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/EquityMethodInvestmentDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#EquityMethodInvestmentDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/EquityMethodInvestmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" 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_019fd756-d1be-7892-8fd6-8144dd28f1a7" 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_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019fd756-d1be-7892-8fd6-8144dd28f1a7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_019fd756-d1be-798c-894e-6df014f691e9" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019fd756-d1be-7892-8fd6-8144dd28f1a7" xlink:to="loc_srt_OwnershipAxis_019fd756-d1be-798c-894e-6df014f691e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019fd756-d1be-798c-894e-6df014f691e9_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_019fd756-d1be-798c-894e-6df014f691e9" xlink:to="loc_srt_OwnershipDomain_019fd756-d1be-798c-894e-6df014f691e9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019fd756-d1be-7027-98b4-e7b189df75ac" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_019fd756-d1be-798c-894e-6df014f691e9" xlink:to="loc_srt_OwnershipDomain_019fd756-d1be-7027-98b4-e7b189df75ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d1be-7b01-9f02-f7bf5e0bf1ac" xlink:href="svc-20260930.xsd#svc_SonestaInternationalHotelsCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_019fd756-d1be-7027-98b4-e7b189df75ac" xlink:to="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d1be-7b01-9f02-f7bf5e0bf1ac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-76d4-9cbc-db431e873cfc" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019fd756-d1be-7892-8fd6-8144dd28f1a7" xlink:to="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-76d4-9cbc-db431e873cfc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-76d4-9cbc-db431e873cfc_default" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-76d4-9cbc-db431e873cfc" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-76d4-9cbc-db431e873cfc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-71af-a34c-6573c7b3fcd4" xlink:href="svc-20260930.xsd#svc_ManagementAgreementContractNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_svc_ManagementAgreementContractNameAxis_019fd756-d1be-76d4-9cbc-db431e873cfc" xlink:to="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-71af-a34c-6573c7b3fcd4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SonestaAgreementMember_019fd756-d1be-7b97-a363-b75cc5e6a8a4" xlink:href="svc-20260930.xsd#svc_SonestaAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ManagementAgreementContractNameDomain_019fd756-d1be-71af-a34c-6573c7b3fcd4" xlink:to="loc_svc_SonestaAgreementMember_019fd756-d1be-7b97-a363-b75cc5e6a8a4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019fd756-d1be-7706-aff3-4bdf542b2e60" 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_ScheduleOfEquityMethodInvestmentsTable_019fd756-d1be-7892-8fd6-8144dd28f1a7" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019fd756-d1be-7706-aff3-4bdf542b2e60" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019fd756-d1be-7706-aff3-4bdf542b2e60_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_019fd756-d1be-7706-aff3-4bdf542b2e60" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019fd756-d1be-7706-aff3-4bdf542b2e60_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019fd756-d1be-775d-a4b7-4f8bc3f89452" 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_019fd756-d1be-7706-aff3-4bdf542b2e60" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019fd756-d1be-775d-a4b7-4f8bc3f89452" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d1be-7259-9d50-61e16ac9861f" xlink:href="svc-20260930.xsd#svc_SonestaInternationalHotelsCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019fd756-d1be-775d-a4b7-4f8bc3f89452" xlink:to="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d1be-7259-9d50-61e16ac9861f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_019fd756-d1be-7ad8-b4ce-aba3fdf6c166" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_019fd756-d1be-7ad8-b4ce-aba3fdf6c166" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019fd756-d1be-78cb-8182-42b22c9a14da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_us-gaap_EquityMethodInvestments_019fd756-d1be-78cb-8182-42b22c9a14da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_EquityMethodInvestmentCostBasisAdjustment_019fd756-d1be-72c6-abd6-e58b9928e036" xlink:href="svc-20260930.xsd#svc_EquityMethodInvestmentCostBasisAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_svc_EquityMethodInvestmentCostBasisAdjustment_019fd756-d1be-72c6-abd6-e58b9928e036" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_EquityMethodInvestmentAmortizationPeriod_019fd756-d1be-77e1-839d-d290d93a6281" xlink:href="svc-20260930.xsd#svc_EquityMethodInvestmentAmortizationPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_svc_EquityMethodInvestmentAmortizationPeriod_019fd756-d1be-77e1-839d-d290d93a6281" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfAcquisitionCosts_019fd756-d1be-7011-b5ed-446ca6937fa6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfAcquisitionCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_us-gaap_AmortizationOfAcquisitionCosts_019fd756-d1be-7011-b5ed-446ca6937fa6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019fd756-d1be-7a11-80b6-309756cb717e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019fd756-d1be-7a11-80b6-309756cb717e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilities_019fd756-d1be-787c-9058-b4156fcc5658" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_us-gaap_OtherLiabilities_019fd756-d1be-787c-9058-b4156fcc5658" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_IncreaseDecreaseInCostOfGoodsAndServicesSold_019fd756-d1be-7578-b4cf-9e72c72c8d02" xlink:href="svc-20260930.xsd#svc_IncreaseDecreaseInCostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_svc_IncreaseDecreaseInCostOfGoodsAndServicesSold_019fd756-d1be-7578-b4cf-9e72c72c8d02" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DeferredGain_019fd756-d1be-7f7e-aae9-0fa865be8122" xlink:href="svc-20260930.xsd#svc_DeferredGain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019fd756-d1be-7ff2-80a5-bacec240270f" xlink:to="loc_svc_DeferredGain_019fd756-d1be-7f7e-aae9-0fa865be8122" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/IndebtednessNarrativeDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#IndebtednessNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/IndebtednessNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" 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_019fd756-d1be-7335-8947-266bd65c8d93" 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_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_DebtInstrumentTable_019fd756-d1be-7335-8947-266bd65c8d93" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_01a0b4f4-964e-72ca-bee1-291941aacac1" 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_019fd756-d1be-7335-8947-266bd65c8d93" xlink:to="loc_us-gaap_DebtInstrumentAxis_01a0b4f4-964e-72ca-bee1-291941aacac1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0b4f4-964e-72ca-bee1-291941aacac1_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_01a0b4f4-964e-72ca-bee1-291941aacac1" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0b4f4-964e-72ca-bee1-291941aacac1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_01a0b4f4-964e-7a85-ad42-e99de93e7b6c" 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_01a0b4f4-964e-72ca-bee1-291941aacac1" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_01a0b4f4-964e-7a85-ad42-e99de93e7b6c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorUnsecuredNotesMember_01a0b4f4-964e-7b33-9051-2ef394a73b07" xlink:href="svc-20260930.xsd#svc_SeniorUnsecuredNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0b4f4-964e-7a85-ad42-e99de93e7b6c" xlink:to="loc_svc_SeniorUnsecuredNotesMember_01a0b4f4-964e-7b33-9051-2ef394a73b07" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes4.95PercentDue2027Member_01a0b4f9-435a-71bc-9acc-60363d851d82" xlink:href="svc-20260930.xsd#svc_SeniorNotes4.95PercentDue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_SeniorUnsecuredNotesMember_01a0b4f4-964e-7b33-9051-2ef394a73b07" xlink:to="loc_svc_SeniorNotes4.95PercentDue2027Member_01a0b4f9-435a-71bc-9acc-60363d851d82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes8.375PercentDue2029Member_01a0b4f9-435a-7353-aa58-d28912a38249" xlink:href="svc-20260930.xsd#svc_SeniorNotes8.375PercentDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_SeniorUnsecuredNotesMember_01a0b4f4-964e-7b33-9051-2ef394a73b07" xlink:to="loc_svc_SeniorNotes8.375PercentDue2029Member_01a0b4f9-435a-7353-aa58-d28912a38249" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes550PercentDue2027Member_01a0b4f9-435a-790b-a182-053988777762" xlink:href="svc-20260930.xsd#svc_SeniorNotes550PercentDue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_SeniorUnsecuredNotesMember_01a0b4f4-964e-7b33-9051-2ef394a73b07" xlink:to="loc_svc_SeniorNotes550PercentDue2027Member_01a0b4f9-435a-790b-a182-053988777762" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorSecuredNotesMember_01a0b4f4-964e-7dcb-8136-e6025613ae15" xlink:href="svc-20260930.xsd#svc_SeniorSecuredNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0b4f4-964e-7a85-ad42-e99de93e7b6c" xlink:to="loc_svc_SeniorSecuredNotesMember_01a0b4f4-964e-7dcb-8136-e6025613ae15" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_01a0b4fd-a4ed-7b5a-91f9-83ea1562276f" xlink:href="svc-20260930.xsd#svc_NetLeaseMortgageNotes5.60PercentDue2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0b4f4-964e-7a85-ad42-e99de93e7b6c" xlink:to="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_01a0b4fd-a4ed-7b5a-91f9-83ea1562276f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassACouponRate5.15Member_01a0b4fd-a4ed-7ec9-9f36-c50a2f98f592" xlink:href="svc-20260930.xsd#svc_ClassACouponRate5.15Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_01a0b4fd-a4ed-7b5a-91f9-83ea1562276f" xlink:to="loc_svc_ClassACouponRate5.15Member_01a0b4fd-a4ed-7ec9-9f36-c50a2f98f592" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassBCouponRate5.55Member_01a0b4fd-a4ed-74c4-81d0-10f516589477" xlink:href="svc-20260930.xsd#svc_ClassBCouponRate5.55Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_01a0b4fd-a4ed-7b5a-91f9-83ea1562276f" xlink:to="loc_svc_ClassBCouponRate5.55Member_01a0b4fd-a4ed-74c4-81d0-10f516589477" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_01a0b4fd-74ee-7f10-82ac-e8a3c3bae20e" xlink:href="svc-20260930.xsd#svc_NetLeaseMortgageNotes5.96PercentDue2031Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_01a0b4f4-964e-7a85-ad42-e99de93e7b6c" xlink:to="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_01a0b4fd-74ee-7f10-82ac-e8a3c3bae20e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassACouponRate5.16Member_01a0b4fd-a4ed-73ec-b0df-5aee779aee40" xlink:href="svc-20260930.xsd#svc_ClassACouponRate5.16Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_01a0b4fd-74ee-7f10-82ac-e8a3c3bae20e" xlink:to="loc_svc_ClassACouponRate5.16Member_01a0b4fd-a4ed-73ec-b0df-5aee779aee40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassBCouponRate5.80Member_01a0b4fd-a4ed-70e5-9475-84fdd0942002" xlink:href="svc-20260930.xsd#svc_ClassBCouponRate5.80Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_01a0b4fd-74ee-7f10-82ac-e8a3c3bae20e" xlink:to="loc_svc_ClassBCouponRate5.80Member_01a0b4fd-a4ed-70e5-9475-84fdd0942002" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_01a0b4f4-964e-7da6-bcd0-106c3a70f344" 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_019fd756-d1be-7335-8947-266bd65c8d93" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_01a0b4f4-964e-7da6-bcd0-106c3a70f344" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0b4f4-964e-7da6-bcd0-106c3a70f344_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_01a0b4f4-964e-7da6-bcd0-106c3a70f344" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0b4f4-964e-7da6-bcd0-106c3a70f344_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_01a0b4f4-964e-7d96-9fd6-d244d0dba2a8" 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_01a0b4f4-964e-7da6-bcd0-106c3a70f344" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_01a0b4f4-964e-7d96-9fd6-d244d0dba2a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_01a0b4f4-964e-770f-b6d1-a3dff69b910f" 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_01a0b4f4-964e-7d96-9fd6-d244d0dba2a8" xlink:to="loc_us-gaap_SeniorNotesMember_01a0b4f4-964e-770f-b6d1-a3dff69b910f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgagesMember_01a0b4f4-964e-7886-b9c2-6d34eb2629b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgagesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b4f4-964e-7d96-9fd6-d244d0dba2a8" xlink:to="loc_us-gaap_MortgagesMember_01a0b4f4-964e-7886-b9c2-6d34eb2629b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_01a0b4f7-6ff4-733f-ae98-cd3256c877ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b4f4-964e-7d96-9fd6-d244d0dba2a8" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_01a0b4f7-6ff4-733f-ae98-cd3256c877ac" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_VariableFundingNotesMember_01a0b4fd-dda0-7972-974e-675820c2ea94" xlink:href="svc-20260930.xsd#svc_VariableFundingNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_01a0b4f4-964e-7d96-9fd6-d244d0dba2a8" xlink:to="loc_svc_VariableFundingNotesMember_01a0b4fd-dda0-7972-974e-675820c2ea94" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_01a0b4f7-6ff4-7a3e-ba94-c7a41f943b08" 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_DebtInstrumentTable_019fd756-d1be-7335-8947-266bd65c8d93" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_01a0b4f7-6ff4-7a3e-ba94-c7a41f943b08" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a0b4f7-6ff4-7a3e-ba94-c7a41f943b08_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_01a0b4f7-6ff4-7a3e-ba94-c7a41f943b08" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a0b4f7-6ff4-7a3e-ba94-c7a41f943b08_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a0b4f7-6ff4-79ca-804f-7f809a1bfec8" 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_01a0b4f7-6ff4-7a3e-ba94-c7a41f943b08" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a0b4f7-6ff4-79ca-804f-7f809a1bfec8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_01a0b4f7-6ff4-78db-aecb-47f226ab441a" 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_01a0b4f7-6ff4-79ca-804f-7f809a1bfec8" xlink:to="loc_us-gaap_SubsequentEventMember_01a0b4f7-6ff4-78db-aecb-47f226ab441a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a0b4f8-580f-71ce-900e-788ed326e927" 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_DebtInstrumentTable_019fd756-d1be-7335-8947-266bd65c8d93" xlink:to="loc_srt_RangeAxis_01a0b4f8-580f-71ce-900e-788ed326e927" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a0b4f8-580f-71ce-900e-788ed326e927_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_01a0b4f8-580f-71ce-900e-788ed326e927" xlink:to="loc_srt_RangeMember_01a0b4f8-580f-71ce-900e-788ed326e927_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a0b4f8-580f-73e1-a3bc-1d33e3edc334" 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_01a0b4f8-580f-71ce-900e-788ed326e927" xlink:to="loc_srt_RangeMember_01a0b4f8-580f-73e1-a3bc-1d33e3edc334" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a0b4f8-580f-7256-9a77-f0ccf7dd4280" 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_01a0b4f8-580f-73e1-a3bc-1d33e3edc334" xlink:to="loc_srt_MinimumMember_01a0b4f8-580f-7256-9a77-f0ccf7dd4280" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a0b4f8-580f-7192-ab60-990ee59b79dc" 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_01a0b4f8-580f-73e1-a3bc-1d33e3edc334" xlink:to="loc_srt_MaximumMember_01a0b4f8-580f-7192-ab60-990ee59b79dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_01a0b4f8-c7ce-72d6-94d3-78597ba4d38c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019fd756-d1be-7335-8947-266bd65c8d93" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_01a0b4f8-c7ce-72d6-94d3-78597ba4d38c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a0b4f8-c7ce-72d6-94d3-78597ba4d38c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_01a0b4f8-c7ce-72d6-94d3-78597ba4d38c" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a0b4f8-c7ce-72d6-94d3-78597ba4d38c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a0b4f8-c7ce-790b-8733-027af562ea81" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_01a0b4f8-c7ce-72d6-94d3-78597ba4d38c" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a0b4f8-c7ce-790b-8733-027af562ea81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_01a0b4f8-c7ce-7ce4-941f-41cd58fca506" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a0b4f8-c7ce-790b-8733-027af562ea81" xlink:to="loc_svc_NetLeasePropertyMember_01a0b4f8-c7ce-7ce4-941f-41cd58fca506" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_01a0b4f8-c7ce-7f94-acb6-e0af92abb0dd" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_01a0b4f8-c7ce-790b-8733-027af562ea81" xlink:to="loc_srt_HotelMember_01a0b4f8-c7ce-7f94-acb6-e0af92abb0dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_01a0b4fd-74ee-7acf-b1d7-7f74808f2d8e" 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_DebtInstrumentTable_019fd756-d1be-7335-8947-266bd65c8d93" xlink:to="loc_srt_CounterpartyNameAxis_01a0b4fd-74ee-7acf-b1d7-7f74808f2d8e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a0b4fd-74ee-7acf-b1d7-7f74808f2d8e_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_01a0b4fd-74ee-7acf-b1d7-7f74808f2d8e" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a0b4fd-74ee-7acf-b1d7-7f74808f2d8e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a0b4fd-74ee-7ff0-8ae3-96abaf4d0928" 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_01a0b4fd-74ee-7acf-b1d7-7f74808f2d8e" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a0b4fd-74ee-7ff0-8ae3-96abaf4d0928" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ServicePropertiesTrustMember_01a0b4fd-74ee-783f-bdaa-a514acaa4483" xlink:href="svc-20260930.xsd#svc_ServicePropertiesTrustMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a0b4fd-74ee-7ff0-8ae3-96abaf4d0928" xlink:to="loc_svc_ServicePropertiesTrustMember_01a0b4fd-74ee-783f-bdaa-a514acaa4483" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_01a0b4fd-a4ed-77b1-8a1e-aa906061112f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019fd756-d1be-7335-8947-266bd65c8d93" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_01a0b4fd-a4ed-77b1-8a1e-aa906061112f" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_01a0b4fd-a4ed-77b1-8a1e-aa906061112f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_01a0b4fd-a4ed-77b1-8a1e-aa906061112f" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_01a0b4fd-a4ed-77b1-8a1e-aa906061112f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_01a0b4fd-a4ed-71e1-8e13-6b8ba5e14670" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_01a0b4fd-a4ed-77b1-8a1e-aa906061112f" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_01a0b4fd-a4ed-71e1-8e13-6b8ba5e14670" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_01a0b4fd-a4ed-7893-bd96-95b7fb4470b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_01a0b4fd-a4ed-71e1-8e13-6b8ba5e14670" xlink:to="loc_us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember_01a0b4fd-a4ed-7893-bd96-95b7fb4470b4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_01a0b4fd-a4ed-7bd9-b8df-1fcd192123fb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019fd756-d1be-7335-8947-266bd65c8d93" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_01a0b4fd-a4ed-7bd9-b8df-1fcd192123fb" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_01a0b4fd-a4ed-7bd9-b8df-1fcd192123fb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_01a0b4fd-a4ed-7bd9-b8df-1fcd192123fb" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_01a0b4fd-a4ed-7bd9-b8df-1fcd192123fb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_01a0b4fd-a4ed-7e2b-b0dd-f68320072d55" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_01a0b4fd-a4ed-7bd9-b8df-1fcd192123fb" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_01a0b4fd-a4ed-7e2b-b0dd-f68320072d55" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateDispositionsMember_01a0b4fd-a4ed-7f21-a0cf-f4d39de77569" xlink:href="svc-20260930.xsd#svc_RealEstateDispositionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_01a0b4fd-a4ed-7e2b-b0dd-f68320072d55" xlink:to="loc_svc_RealEstateDispositionsMember_01a0b4fd-a4ed-7f21-a0cf-f4d39de77569" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotes_01a0b4f4-964e-7ee3-8ce5-d0f23a922fc9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_SeniorNotes_01a0b4f4-964e-7ee3-8ce5-d0f23a922fc9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_01a0b4f4-964e-7f1f-aa61-6338b2b6bc0d" 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_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_01a0b4f4-964e-7f1f-aa61-6338b2b6bc0d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_01a0b4f8-580f-786b-b388-6c9a9c1ecbfa" 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_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_LineOfCredit_01a0b4f8-580f-786b-b388-6c9a9c1ecbfa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a0b4f7-6ff4-75bc-8103-c1db10067c97" 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_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a0b4f7-6ff4-75bc-8103-c1db10067c97" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DebtInstrumentExtensionOptionNumber_01a0b4f7-6ff4-7884-b44a-fd43f24729ef" xlink:href="svc-20260930.xsd#svc_DebtInstrumentExtensionOptionNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_svc_DebtInstrumentExtensionOptionNumber_01a0b4f7-6ff4-7884-b44a-fd43f24729ef" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DebtInstrumentExtensionOptionTerm_01a0b4f7-6ff4-782e-b31a-dcb170ff9c5f" xlink:href="svc-20260930.xsd#svc_DebtInstrumentExtensionOptionTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_svc_DebtInstrumentExtensionOptionTerm_01a0b4f7-6ff4-782e-b31a-dcb170ff9c5f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_01a0b4f8-580f-7629-ae49-77a6be8ea19d" 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_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_01a0b4f8-580f-7629-ae49-77a6be8ea19d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DebtInstrumentCovenantComplianceLeverageRatioLimit_01a0b4f8-580f-731e-9b80-b8038e738874" xlink:href="svc-20260930.xsd#svc_DebtInstrumentCovenantComplianceLeverageRatioLimit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_svc_DebtInstrumentCovenantComplianceLeverageRatioLimit_01a0b4f8-580f-731e-9b80-b8038e738874" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_01a0b4f8-580f-7821-8769-f0d76f5c5782" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityCommitmentFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_LineOfCreditFacilityCommitmentFeePercentage_01a0b4f8-580f-7821-8769-f0d76f5c5782" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_01a0b4f8-580f-7f8f-b156-47bc968e12ec" 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_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_01a0b4f8-580f-7f8f-b156-47bc968e12ec" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtWeightedAverageInterestRateOverTime_01a0b4f8-580f-76fe-a0f5-877b27f0911e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtWeightedAverageInterestRateOverTime"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_LongTermDebtWeightedAverageInterestRateOverTime_01a0b4f8-580f-76fe-a0f5-877b27f0911e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DebtInstrumentCollateralProperties_01a0b4f8-c7ce-7503-9d65-7e144115d7eb" xlink:href="svc-20260930.xsd#svc_DebtInstrumentCollateralProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_svc_DebtInstrumentCollateralProperties_01a0b4f8-c7ce-7503-9d65-7e144115d7eb" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCollateralAmount_01a0b4f8-c7ce-7f1f-ad27-296d101ff0a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCollateralAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_DebtInstrumentCollateralAmount_01a0b4f8-c7ce-7f1f-ad27-296d101ff0a8" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRepurchasedFaceAmount_01a0b4f9-435a-7d35-9987-57bd35a829cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRepurchasedFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_DebtInstrumentRepurchasedFaceAmount_01a0b4f9-435a-7d35-9987-57bd35a829cd" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_01a0b4f9-435a-7b6b-9b73-6078d5c014da" 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_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_01a0b4f9-435a-7b6b-9b73-6078d5c014da" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RedemptionPremium_01a0b4f9-435a-7510-a48c-f9e02b94c1af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RedemptionPremium"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_RedemptionPremium_01a0b4f9-435a-7510-a48c-f9e02b94c1af" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_01a0b4f9-435a-7a40-aae0-1836617c1ce0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_01a0b4f9-435a-7a40-aae0-1836617c1ce0" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DebtInstrumentGrossBookValue_01a0b4fd-74ee-79cb-b35c-e52d5c7be717" xlink:href="svc-20260930.xsd#svc_DebtInstrumentGrossBookValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_svc_DebtInstrumentGrossBookValue_01a0b4fd-74ee-79cb-b35c-e52d5c7be717" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OperatingAgreementAnnualRentAndReturn_01a0b4fd-74ee-7ef2-8fa0-6e327810c24b" xlink:href="svc-20260930.xsd#svc_OperatingAgreementAnnualRentAndReturn"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_svc_OperatingAgreementAnnualRentAndReturn_01a0b4fd-74ee-7ef2-8fa0-6e327810c24b" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DebtInstrumentMonthlyRedemptionPricePercentage_01a0b4fd-a4ed-7356-bad1-2851b8827de4" xlink:href="svc-20260930.xsd#svc_DebtInstrumentMonthlyRedemptionPricePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_svc_DebtInstrumentMonthlyRedemptionPricePercentage_01a0b4fd-a4ed-7356-bad1-2851b8827de4" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_DebtInstrumentCovenantRedemptionPeriod_01a0b4fd-a4ed-726f-8828-2cf85b2163dd" xlink:href="svc-20260930.xsd#svc_DebtInstrumentCovenantRedemptionPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_svc_DebtInstrumentCovenantRedemptionPeriod_01a0b4fd-a4ed-726f-8828-2cf85b2163dd" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_01a0b4fd-dda0-76f5-b1db-175442abafd1" 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_019fd756-d1be-79db-9ff8-87c631593f4b" xlink:to="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_01a0b4fd-dda0-76f5-b1db-175442abafd1" xlink:type="arc" order="21"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/IndebtednessScheduleofNetLeaseMortgageNotesDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#IndebtednessScheduleofNetLeaseMortgageNotesDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/IndebtednessScheduleofNetLeaseMortgageNotesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-7163-b660-4546067a906e" 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_019fd756-d1be-77c4-8d37-18c1e3a4ac12" 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_019fd756-d1be-7163-b660-4546067a906e" xlink:to="loc_us-gaap_DebtInstrumentTable_019fd756-d1be-77c4-8d37-18c1e3a4ac12" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019fd756-d1be-73ab-ba4c-77f3312a382b" 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_019fd756-d1be-77c4-8d37-18c1e3a4ac12" xlink:to="loc_us-gaap_DebtInstrumentAxis_019fd756-d1be-73ab-ba4c-77f3312a382b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d1be-73ab-ba4c-77f3312a382b_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_019fd756-d1be-73ab-ba4c-77f3312a382b" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d1be-73ab-ba4c-77f3312a382b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d1be-73de-a83a-b22e15fad8bf" 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_019fd756-d1be-73ab-ba4c-77f3312a382b" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d1be-73de-a83a-b22e15fad8bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_019fd756-d1be-75f6-877f-63fdbc94359f" xlink:href="svc-20260930.xsd#svc_NetLeaseMortgageNotes5.60PercentDue2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d1be-73de-a83a-b22e15fad8bf" xlink:to="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_019fd756-d1be-75f6-877f-63fdbc94359f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassACouponRate5.15Member_019fd756-d1be-74f2-aa39-98db7870980d" xlink:href="svc-20260930.xsd#svc_ClassACouponRate5.15Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_019fd756-d1be-75f6-877f-63fdbc94359f" xlink:to="loc_svc_ClassACouponRate5.15Member_019fd756-d1be-74f2-aa39-98db7870980d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassBCouponRate5.55Member_019fd756-d1be-78eb-aee5-4182ba0ca6dd" xlink:href="svc-20260930.xsd#svc_ClassBCouponRate5.55Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_019fd756-d1be-75f6-877f-63fdbc94359f" xlink:to="loc_svc_ClassBCouponRate5.55Member_019fd756-d1be-78eb-aee5-4182ba0ca6dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassCCouponRate6.70Member_019fd756-d1be-7f10-b3b4-4683a2515470" xlink:href="svc-20260930.xsd#svc_ClassCCouponRate6.70Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_019fd756-d1be-75f6-877f-63fdbc94359f" xlink:to="loc_svc_ClassCCouponRate6.70Member_019fd756-d1be-7f10-b3b4-4683a2515470" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_019fd756-d1be-7323-b8cb-31e6241ce1d1" xlink:href="svc-20260930.xsd#svc_NetLeaseMortgageNotes5.96PercentDue2031Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d1be-73de-a83a-b22e15fad8bf" xlink:to="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_019fd756-d1be-7323-b8cb-31e6241ce1d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassACouponRate5.16Member_019fd756-d1be-79dc-92ce-9e7c7a3a1488" xlink:href="svc-20260930.xsd#svc_ClassACouponRate5.16Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_019fd756-d1be-7323-b8cb-31e6241ce1d1" xlink:to="loc_svc_ClassACouponRate5.16Member_019fd756-d1be-79dc-92ce-9e7c7a3a1488" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassBCouponRate5.80Member_019fd756-d1be-7594-b4cb-f741a39a4a09" xlink:href="svc-20260930.xsd#svc_ClassBCouponRate5.80Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_019fd756-d1be-7323-b8cb-31e6241ce1d1" xlink:to="loc_svc_ClassBCouponRate5.80Member_019fd756-d1be-7594-b4cb-f741a39a4a09" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ClassMCouponRate7.55Member_019fd756-d1be-7a22-b483-99a6b3af9877" xlink:href="svc-20260930.xsd#svc_ClassMCouponRate7.55Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_019fd756-d1be-7323-b8cb-31e6241ce1d1" xlink:to="loc_svc_ClassMCouponRate7.55Member_019fd756-d1be-7a22-b483-99a6b3af9877" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019fd756-d1be-7fe3-99a6-f3162b0821b7" 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_019fd756-d1be-77c4-8d37-18c1e3a4ac12" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019fd756-d1be-7fe3-99a6-f3162b0821b7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019fd756-d1be-7fe3-99a6-f3162b0821b7_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_019fd756-d1be-7fe3-99a6-f3162b0821b7" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019fd756-d1be-7fe3-99a6-f3162b0821b7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019fd756-d1be-74a7-8d4a-b5f69ceb7ef7" 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_019fd756-d1be-7fe3-99a6-f3162b0821b7" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019fd756-d1be-74a7-8d4a-b5f69ceb7ef7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgagesMember_019fd756-d1be-766e-b4c7-a3fbec214392" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgagesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019fd756-d1be-74a7-8d4a-b5f69ceb7ef7" xlink:to="loc_us-gaap_MortgagesMember_019fd756-d1be-766e-b4c7-a3fbec214392" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_019fd756-d1be-713a-b019-27a91b92b760" 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_019fd756-d1be-7163-b660-4546067a906e" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_019fd756-d1be-713a-b019-27a91b92b760" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019fd756-d1be-7fa7-a257-2b717fe4cbc7" 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_019fd756-d1be-7163-b660-4546067a906e" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019fd756-d1be-7fa7-a257-2b717fe4cbc7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTerm_019fd756-d1be-745d-8ba5-45dc65805b34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019fd756-d1be-7163-b660-4546067a906e" xlink:to="loc_us-gaap_DebtInstrumentTerm_019fd756-d1be-745d-8ba5-45dc65805b34" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/ShareholdersEquityEquityOfferingDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#ShareholdersEquityEquityOfferingDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/ShareholdersEquityEquityOfferingDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-7edd-959d-56c115f57fb6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_019fd756-d1be-77c1-891a-5dac790c9a74" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-7edd-959d-56c115f57fb6" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_019fd756-d1be-77c1-891a-5dac790c9a74" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_019fd756-d1be-7321-9567-a43a8e3c9492" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019fd756-d1be-77c1-891a-5dac790c9a74" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_019fd756-d1be-7321-9567-a43a8e3c9492" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d1be-7321-9567-a43a8e3c9492_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_019fd756-d1be-7321-9567-a43a8e3c9492" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d1be-7321-9567-a43a8e3c9492_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d1be-7ef8-b349-eec4bf0372dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_019fd756-d1be-7321-9567-a43a8e3c9492" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d1be-7ef8-b349-eec4bf0372dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PublicStockOfferingMember_019fd756-d1be-7bc0-a2d2-05924e7a985e" xlink:href="svc-20260930.xsd#svc_PublicStockOfferingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d1be-7ef8-b349-eec4bf0372dd" xlink:to="loc_svc_PublicStockOfferingMember_019fd756-d1be-7bc0-a2d2-05924e7a985e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PublicStockOfferingPriorToReverseStockSplitMember_019fd756-d1be-7c86-8e5c-25da0240ec7f" xlink:href="svc-20260930.xsd#svc_PublicStockOfferingPriorToReverseStockSplitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d1be-7ef8-b349-eec4bf0372dd" xlink:to="loc_svc_PublicStockOfferingPriorToReverseStockSplitMember_019fd756-d1be-7c86-8e5c-25da0240ec7f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OverAllotmentOptionMember_019fd756-d1be-79a3-a5ba-4cac7bcef22a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OverAllotmentOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d1be-7ef8-b349-eec4bf0372dd" xlink:to="loc_us-gaap_OverAllotmentOptionMember_019fd756-d1be-79a3-a5ba-4cac7bcef22a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_OverAllotmentOptionPriorToReverseStockSplitMember_019fd756-d1be-7beb-a809-69c3d17b171e" xlink:href="svc-20260930.xsd#svc_OverAllotmentOptionPriorToReverseStockSplitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d1be-7ef8-b349-eec4bf0372dd" xlink:to="loc_svc_OverAllotmentOptionPriorToReverseStockSplitMember_019fd756-d1be-7beb-a809-69c3d17b171e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_019fd756-d1be-79d8-899d-502a22d90c5e" 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_ClassOfStockLineItems_019fd756-d1be-7edd-959d-56c115f57fb6" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_019fd756-d1be-79d8-899d-502a22d90c5e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_019fd756-d1be-7cbd-b707-8812a46027c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-7edd-959d-56c115f57fb6" xlink:to="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_019fd756-d1be-7cbd-b707-8812a46027c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_019fd756-d1be-72ba-a7f5-79b1a4be2325" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-7edd-959d-56c115f57fb6" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_019fd756-d1be-72ba-a7f5-79b1a4be2325" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_019fd756-d1be-7ed6-938a-8717d9c5d049" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-7edd-959d-56c115f57fb6" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_019fd756-d1be-7ed6-938a-8717d9c5d049" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/ShareholdersEquityShareAwardsandSharePurchasesDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#ShareholdersEquityShareAwardsandSharePurchasesDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/ShareholdersEquityShareAwardsandSharePurchasesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-768b-99f8-a4e7b7e89827" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_019fd756-d1be-70e3-a21b-64d7aaae19e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-768b-99f8-a4e7b7e89827" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_019fd756-d1be-70e3-a21b-64d7aaae19e6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019fd756-d1be-7053-9fc2-7ca58e47abdd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019fd756-d1be-70e3-a21b-64d7aaae19e6" xlink:to="loc_us-gaap_AwardTypeAxis_019fd756-d1be-7053-9fc2-7ca58e47abdd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fd756-d1be-7053-9fc2-7ca58e47abdd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019fd756-d1be-7053-9fc2-7ca58e47abdd" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fd756-d1be-7053-9fc2-7ca58e47abdd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fd756-d1be-74e4-b3a1-f03fe1f8939c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019fd756-d1be-7053-9fc2-7ca58e47abdd" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fd756-d1be-74e4-b3a1-f03fe1f8939c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ShareAwardPlansMember_019fd756-d1be-7060-a78e-76c1bb7fc000" xlink:href="svc-20260930.xsd#svc_ShareAwardPlansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fd756-d1be-74e4-b3a1-f03fe1f8939c" xlink:to="loc_svc_ShareAwardPlansMember_019fd756-d1be-7060-a78e-76c1bb7fc000" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019fd756-d1be-7574-bcea-c08b3cc1e70a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-768b-99f8-a4e7b7e89827" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019fd756-d1be-7574-bcea-c08b3cc1e70a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019fd756-d1be-7498-9d5d-e19d90a404a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-768b-99f8-a4e7b7e89827" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_019fd756-d1be-7498-9d5d-e19d90a404a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NumberOfNewTrustees_019fd756-d1be-7d1d-91ad-3b6f02f68020" xlink:href="svc-20260930.xsd#svc_NumberOfNewTrustees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-768b-99f8-a4e7b7e89827" xlink:to="loc_svc_NumberOfNewTrustees_019fd756-d1be-7d1d-91ad-3b6f02f68020" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_019fd756-d1be-712b-a200-9442da60e2a1" 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_ClassOfStockLineItems_019fd756-d1be-768b-99f8-a4e7b7e89827" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_019fd756-d1be-712b-a200-9442da60e2a1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_019fd756-d1be-73f0-8911-69fc874f5815" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockAcquiredAverageCostPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d1be-768b-99f8-a4e7b7e89827" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_019fd756-d1be-73f0-8911-69fc874f5815" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/ShareholdersEquityDistributionsDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#ShareholdersEquityDistributionsDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/ShareholdersEquityDistributionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_019fd756-d25c-786e-9238-3078c1dd517f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_019fd756-d1be-74f7-ab67-3b0fe08ddb3f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d25c-786e-9238-3078c1dd517f" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_019fd756-d1be-74f7-ab67-3b0fe08ddb3f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_019fd756-d1be-755f-b8d0-ee6455862948" 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_ScheduleOfStockByClassTable_019fd756-d1be-74f7-ab67-3b0fe08ddb3f" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_019fd756-d1be-755f-b8d0-ee6455862948" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-755f-b8d0-ee6455862948_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_019fd756-d1be-755f-b8d0-ee6455862948" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d1be-755f-b8d0-ee6455862948_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d25c-719c-97dd-5ac3d3efe629" 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_019fd756-d1be-755f-b8d0-ee6455862948" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019fd756-d25c-719c-97dd-5ac3d3efe629" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_019fd756-d25c-70ea-8a96-8662866cb17f" 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_019fd756-d25c-719c-97dd-5ac3d3efe629" xlink:to="loc_us-gaap_SubsequentEventMember_019fd756-d25c-70ea-8a96-8662866cb17f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_019fd756-d25c-7ffd-99e2-361a1ce6bac4" 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_ClassOfStockLineItems_019fd756-d25c-786e-9238-3078c1dd517f" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_019fd756-d25c-7ffd-99e2-361a1ce6bac4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStockCash_019fd756-d25c-7a88-b2fc-040f7703c925" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStockCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019fd756-d25c-786e-9238-3078c1dd517f" xlink:to="loc_us-gaap_DividendsCommonStockCash_019fd756-d25c-7a88-b2fc-040f7703c925" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/BusinessandPropertyManagementAgreementswithRMRNarrativeDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#BusinessandPropertyManagementAgreementswithRMRNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/BusinessandPropertyManagementAgreementswithRMRNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-77df-9287-5c6891b27e8c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstatePropertiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-7f1d-aeae-d68aa5353f76" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRealEstatePropertiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-77df-9287-5c6891b27e8c" xlink:to="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-7f1d-aeae-d68aa5353f76" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fd756-d25c-7df3-835c-b843b3dffe0c" 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_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-7f1d-aeae-d68aa5353f76" xlink:to="loc_srt_CounterpartyNameAxis_019fd756-d25c-7df3-835c-b843b3dffe0c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7df3-835c-b843b3dffe0c_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_019fd756-d25c-7df3-835c-b843b3dffe0c" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7df3-835c-b843b3dffe0c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7377-a8bf-f8e632c3abe1" 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_019fd756-d25c-7df3-835c-b843b3dffe0c" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7377-a8bf-f8e632c3abe1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ReitManagementAndResearchMember_019fd756-d25c-7f85-b9cd-60aeb2ded167" xlink:href="svc-20260930.xsd#svc_ReitManagementAndResearchMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7377-a8bf-f8e632c3abe1" xlink:to="loc_svc_ReitManagementAndResearchMember_019fd756-d25c-7f85-b9cd-60aeb2ded167" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionTypeAxis_019fd756-d25c-7695-9e3c-2b7ff7d97ca8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-7f1d-aeae-d68aa5353f76" xlink:to="loc_us-gaap_TransactionTypeAxis_019fd756-d25c-7695-9e3c-2b7ff7d97ca8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionDomain_019fd756-d25c-7695-9e3c-2b7ff7d97ca8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TransactionTypeAxis_019fd756-d25c-7695-9e3c-2b7ff7d97ca8" xlink:to="loc_us-gaap_TransactionDomain_019fd756-d25c-7695-9e3c-2b7ff7d97ca8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionDomain_019fd756-d25c-74a9-bed6-6d542ae88da2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TransactionTypeAxis_019fd756-d25c-7695-9e3c-2b7ff7d97ca8" xlink:to="loc_us-gaap_TransactionDomain_019fd756-d25c-74a9-bed6-6d542ae88da2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AmendedAndRestatedBusinessManagementAgreementMember_019fd756-d25c-74ba-8a6a-7822207f0799" xlink:href="svc-20260930.xsd#svc_AmendedAndRestatedBusinessManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionDomain_019fd756-d25c-74a9-bed6-6d542ae88da2" xlink:to="loc_svc_AmendedAndRestatedBusinessManagementAgreementMember_019fd756-d25c-74ba-8a6a-7822207f0799" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_019fd756-d25c-7fd2-86ac-51dceb3b50ed" 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_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-7f1d-aeae-d68aa5353f76" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_019fd756-d25c-7fd2-86ac-51dceb3b50ed" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7fd2-86ac-51dceb3b50ed_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_019fd756-d25c-7fd2-86ac-51dceb3b50ed" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7fd2-86ac-51dceb3b50ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7d69-9533-344d37066f98" 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_019fd756-d25c-7fd2-86ac-51dceb3b50ed" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7d69-9533-344d37066f98" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_BusinessManagementAgreementMember_019fd756-d25c-75f9-8fdf-19bbcb353a88" xlink:href="svc-20260930.xsd#svc_BusinessManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7d69-9533-344d37066f98" xlink:to="loc_svc_BusinessManagementAgreementMember_019fd756-d25c-75f9-8fdf-19bbcb353a88" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d25c-7164-b4c5-5ae45c35c8f4" 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_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-7f1d-aeae-d68aa5353f76" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d25c-7164-b4c5-5ae45c35c8f4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7164-b4c5-5ae45c35c8f4_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_019fd756-d25c-7164-b4c5-5ae45c35c8f4" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7164-b4c5-5ae45c35c8f4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7a54-a76c-a7ad532efc92" 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_019fd756-d25c-7164-b4c5-5ae45c35c8f4" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7a54-a76c-a7ad532efc92" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ReitManagementAndResearchMember_019fd756-d25c-7e9a-8c82-492ee51a2d5e" xlink:href="svc-20260930.xsd#svc_ReitManagementAndResearchMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7a54-a76c-a7ad532efc92" xlink:to="loc_svc_ReitManagementAndResearchMember_019fd756-d25c-7e9a-8c82-492ee51a2d5e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityNumberOfEmployees_019fd756-d25c-7bc0-a3f6-15dc7e680376" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityNumberOfEmployees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-77df-9287-5c6891b27e8c" xlink:to="loc_dei_EntityNumberOfEmployees_019fd756-d25c-7bc0-a3f6-15dc7e680376" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NumberOfServiceAgreements_019fd756-d25c-7966-ac40-4700be0d6c98" xlink:href="svc-20260930.xsd#svc_NumberOfServiceAgreements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-77df-9287-5c6891b27e8c" xlink:to="loc_svc_NumberOfServiceAgreements_019fd756-d25c-7966-ac40-4700be0d6c98" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionIncentiveFee_019fd756-d25c-75be-8b08-b56bc47a47aa" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionIncentiveFee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-77df-9287-5c6891b27e8c" xlink:to="loc_svc_RelatedPartyTransactionIncentiveFee_019fd756-d25c-75be-8b08-b56bc47a47aa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionsMeasurementPeriod_019fd756-d25c-716f-8c56-3878b3e0c246" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionsMeasurementPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-77df-9287-5c6891b27e8c" xlink:to="loc_svc_RelatedPartyTransactionsMeasurementPeriod_019fd756-d25c-716f-8c56-3878b3e0c246" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/BusinessandPropertyManagementAgreementswithRMRScheduleofBusinessManagementFeesPropertyManagementFeesandConstructionSupervisionFeesRecognizedDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#BusinessandPropertyManagementAgreementswithRMRScheduleofBusinessManagementFeesPropertyManagementFeesandConstructionSupervisionFeesRecognizedDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/BusinessandPropertyManagementAgreementswithRMRScheduleofBusinessManagementFeesPropertyManagementFeesandConstructionSupervisionFeesRecognizedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-7e3e-b0b3-3fa3c1746ae6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstatePropertiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-72fb-845b-8eaa6186981e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRealEstatePropertiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-7e3e-b0b3-3fa3c1746ae6" xlink:to="loc_us-gaap_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-72fb-845b-8eaa6186981e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_019fd756-d25c-79e7-b1ed-7a67410971d9" 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_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-72fb-845b-8eaa6186981e" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_019fd756-d25c-79e7-b1ed-7a67410971d9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-79e7-b1ed-7a67410971d9_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_019fd756-d25c-79e7-b1ed-7a67410971d9" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-79e7-b1ed-7a67410971d9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7866-993b-2e9583e6685d" 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_019fd756-d25c-79e7-b1ed-7a67410971d9" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7866-993b-2e9583e6685d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_BusinessManagementAgreementMember_019fd756-d25c-7229-8d09-fac70e7f52b2" xlink:href="svc-20260930.xsd#svc_BusinessManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7866-993b-2e9583e6685d" xlink:to="loc_svc_BusinessManagementAgreementMember_019fd756-d25c-7229-8d09-fac70e7f52b2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PropertyManagementAgreementMember_019fd756-d25c-745d-a951-7f6a5d78bab3" xlink:href="svc-20260930.xsd#svc_PropertyManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7866-993b-2e9583e6685d" xlink:to="loc_svc_PropertyManagementAgreementMember_019fd756-d25c-745d-a951-7f6a5d78bab3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PropertyManagementAgreementPropertyManagementFeesMember_019fd756-d25c-7ed8-8c64-2e619d4746fa" xlink:href="svc-20260930.xsd#svc_PropertyManagementAgreementPropertyManagementFeesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_PropertyManagementAgreementMember_019fd756-d25c-745d-a951-7f6a5d78bab3" xlink:to="loc_svc_PropertyManagementAgreementPropertyManagementFeesMember_019fd756-d25c-7ed8-8c64-2e619d4746fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PropertyManagementAgreementConstructionSupervisionFeesMember_019fd756-d25c-7e9d-b4b9-ecc6b247dda4" xlink:href="svc-20260930.xsd#svc_PropertyManagementAgreementConstructionSupervisionFeesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_PropertyManagementAgreementMember_019fd756-d25c-745d-a951-7f6a5d78bab3" xlink:to="loc_svc_PropertyManagementAgreementConstructionSupervisionFeesMember_019fd756-d25c-7e9d-b4b9-ecc6b247dda4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ExpenseReimbursementMember_019fd756-d25c-7d32-bd0b-f3ec4b1bfa22" xlink:href="svc-20260930.xsd#svc_ExpenseReimbursementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fd756-d25c-7866-993b-2e9583e6685d" xlink:to="loc_svc_ExpenseReimbursementMember_019fd756-d25c-7d32-bd0b-f3ec4b1bfa22" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d25c-7d64-a1c6-4f6c887872d7" 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_ScheduleOfRealEstatePropertiesTable_019fd756-d25c-72fb-845b-8eaa6186981e" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d25c-7d64-a1c6-4f6c887872d7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7d64-a1c6-4f6c887872d7_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_019fd756-d25c-7d64-a1c6-4f6c887872d7" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7d64-a1c6-4f6c887872d7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-73a5-8c77-daa3a390540c" 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_019fd756-d25c-7d64-a1c6-4f6c887872d7" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-73a5-8c77-daa3a390540c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ReitManagementAndResearchMember_019fd756-d25c-73eb-8f76-64ae6a56f40e" xlink:href="svc-20260930.xsd#svc_ReitManagementAndResearchMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-73a5-8c77-daa3a390540c" xlink:to="loc_svc_ReitManagementAndResearchMember_019fd756-d25c-73eb-8f76-64ae6a56f40e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_019fd756-d25c-7574-9aaf-6af934ee4e23" 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_RealEstatePropertiesLineItems_019fd756-d25c-7e3e-b0b3-3fa3c1746ae6" xlink:to="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_019fd756-d25c-7574-9aaf-6af934ee4e23" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RelatedPartyTransactionAmortizationOfLiability_019fd756-d25c-73d9-a8e3-8d9beb5b8b32" xlink:href="svc-20260930.xsd#svc_RelatedPartyTransactionAmortizationOfLiability"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RealEstatePropertiesLineItems_019fd756-d25c-7e3e-b0b3-3fa3c1746ae6" xlink:to="loc_svc_RelatedPartyTransactionAmortizationOfLiability_019fd756-d25c-73d9-a8e3-8d9beb5b8b32" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/RelatedPersonTransactionsDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#RelatedPersonTransactionsDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/RelatedPersonTransactionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d25c-7236-a727-5d363364d96d" 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_019fd756-d25c-7cb2-b9e3-bba239f6b115" 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_019fd756-d25c-7236-a727-5d363364d96d" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019fd756-d25c-7cb2-b9e3-bba239f6b115" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fd756-d25c-7cf8-8b93-a8d5eeea6686" 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_019fd756-d25c-7cb2-b9e3-bba239f6b115" xlink:to="loc_srt_CounterpartyNameAxis_019fd756-d25c-7cf8-8b93-a8d5eeea6686" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7cf8-8b93-a8d5eeea6686_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_019fd756-d25c-7cf8-8b93-a8d5eeea6686" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7cf8-8b93-a8d5eeea6686_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7745-8c6a-35e63d2641dd" 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_019fd756-d25c-7cf8-8b93-a8d5eeea6686" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7745-8c6a-35e63d2641dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ReitManagementAndResearchMember_019fd756-d25c-70b3-add6-2be4ccf302ff" xlink:href="svc-20260930.xsd#svc_ReitManagementAndResearchMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7745-8c6a-35e63d2641dd" xlink:to="loc_svc_ReitManagementAndResearchMember_019fd756-d25c-70b3-add6-2be4ccf302ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d25c-79e5-b247-31211acd91ce" xlink:href="svc-20260930.xsd#svc_SonestaInternationalHotelsCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7745-8c6a-35e63d2641dd" xlink:to="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d25c-79e5-b247-31211acd91ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ABPTrustMember_019fd756-d25c-7e3b-88df-6f1056b815be" xlink:href="svc-20260930.xsd#svc_ABPTrustMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fd756-d25c-7745-8c6a-35e63d2641dd" xlink:to="loc_svc_ABPTrustMember_019fd756-d25c-7e3b-88df-6f1056b815be" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionTypeAxis_019fd756-d25c-745b-8e8a-ef6828884581" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019fd756-d25c-7cb2-b9e3-bba239f6b115" xlink:to="loc_us-gaap_TransactionTypeAxis_019fd756-d25c-745b-8e8a-ef6828884581" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionDomain_019fd756-d25c-745b-8e8a-ef6828884581_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TransactionTypeAxis_019fd756-d25c-745b-8e8a-ef6828884581" xlink:to="loc_us-gaap_TransactionDomain_019fd756-d25c-745b-8e8a-ef6828884581_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransactionDomain_019fd756-d25c-7977-91df-5f2c7bf5b86a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TransactionTypeAxis_019fd756-d25c-745b-8e8a-ef6828884581" xlink:to="loc_us-gaap_TransactionDomain_019fd756-d25c-7977-91df-5f2c7bf5b86a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_AmendedAndRestatedBusinessManagementAgreementMember_019fd756-d25c-7a99-be7f-56466360d541" xlink:href="svc-20260930.xsd#svc_AmendedAndRestatedBusinessManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransactionDomain_019fd756-d25c-7977-91df-5f2c7bf5b86a" xlink:to="loc_svc_AmendedAndRestatedBusinessManagementAgreementMember_019fd756-d25c-7a99-be7f-56466360d541" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_019fd756-d25c-797f-8ee4-37c33a7ad782" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019fd756-d25c-7cb2-b9e3-bba239f6b115" xlink:to="loc_srt_OwnershipAxis_019fd756-d25c-797f-8ee4-37c33a7ad782" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019fd756-d25c-797f-8ee4-37c33a7ad782_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_019fd756-d25c-797f-8ee4-37c33a7ad782" xlink:to="loc_srt_OwnershipDomain_019fd756-d25c-797f-8ee4-37c33a7ad782_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019fd756-d25c-732d-a229-b3dd16dfa993" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_019fd756-d25c-797f-8ee4-37c33a7ad782" xlink:to="loc_srt_OwnershipDomain_019fd756-d25c-732d-a229-b3dd16dfa993" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d25c-763b-bc3a-79c32c1675a4" xlink:href="svc-20260930.xsd#svc_SonestaInternationalHotelsCorporationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_019fd756-d25c-732d-a229-b3dd16dfa993" xlink:to="loc_svc_SonestaInternationalHotelsCorporationMember_019fd756-d25c-763b-bc3a-79c32c1675a4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d25c-768e-8841-eca513dd6c2a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019fd756-d25c-7cb2-b9e3-bba239f6b115" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d25c-768e-8841-eca513dd6c2a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-768e-8841-eca513dd6c2a_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d25c-768e-8841-eca513dd6c2a" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-768e-8841-eca513dd6c2a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-7072-929f-e704c0beb2aa" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d25c-768e-8841-eca513dd6c2a" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-7072-929f-e704c0beb2aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d25c-7ffe-866a-40baf96d6abb" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-7072-929f-e704c0beb2aa" xlink:to="loc_srt_HotelMember_019fd756-d25c-7ffe-866a-40baf96d6abb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d25c-7f23-9ea8-245d2a061055" 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_019fd756-d25c-7cb2-b9e3-bba239f6b115" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fd756-d25c-7f23-9ea8-245d2a061055" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7f23-9ea8-245d2a061055_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_019fd756-d25c-7f23-9ea8-245d2a061055" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-7f23-9ea8-245d2a061055_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-762f-a4d4-1ba371031080" 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_019fd756-d25c-7f23-9ea8-245d2a061055" xlink:to="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-762f-a4d4-1ba371031080" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019fd756-d25c-787e-80f4-93bca8b77c4c" 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_019fd756-d25c-762f-a4d4-1ba371031080" xlink:to="loc_us-gaap_RelatedPartyMember_019fd756-d25c-787e-80f4-93bca8b77c4c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_TrusteesChiefExecutiveOfficerChiefFinancialOfficerMember_019fd756-d25c-7cc4-9143-abb03f985163" xlink:href="svc-20260930.xsd#svc_TrusteesChiefExecutiveOfficerChiefFinancialOfficerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019fd756-d25c-762f-a4d4-1ba371031080" xlink:to="loc_svc_TrusteesChiefExecutiveOfficerChiefFinancialOfficerMember_019fd756-d25c-7cc4-9143-abb03f985163" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_019fd756-d25c-7840-a8c5-2ca4830a7dec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019fd756-d25c-7cb2-b9e3-bba239f6b115" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_019fd756-d25c-7840-a8c5-2ca4830a7dec" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d25c-7840-a8c5-2ca4830a7dec_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_019fd756-d25c-7840-a8c5-2ca4830a7dec" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d25c-7840-a8c5-2ca4830a7dec_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d25c-70e5-84f4-da9080f5a321" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_019fd756-d25c-7840-a8c5-2ca4830a7dec" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d25c-70e5-84f4-da9080f5a321" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PublicStockOfferingMember_019fd756-d25c-7af0-8d93-fd7ce1dc4230" xlink:href="svc-20260930.xsd#svc_PublicStockOfferingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d25c-70e5-84f4-da9080f5a321" xlink:to="loc_svc_PublicStockOfferingMember_019fd756-d25c-7af0-8d93-fd7ce1dc4230" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_PublicStockOfferingPriorToReverseStockSplitMember_019fd756-d25c-78fe-b403-e2785d7d62c6" xlink:href="svc-20260930.xsd#svc_PublicStockOfferingPriorToReverseStockSplitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019fd756-d25c-70e5-84f4-da9080f5a321" xlink:to="loc_svc_PublicStockOfferingPriorToReverseStockSplitMember_019fd756-d25c-78fe-b403-e2785d7d62c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NumberOfServiceAgreements_019fd756-d25c-7af9-b0b3-db104bb6a3f2" xlink:href="svc-20260930.xsd#svc_NumberOfServiceAgreements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d25c-7236-a727-5d363364d96d" xlink:to="loc_svc_NumberOfServiceAgreements_019fd756-d25c-7af9-b0b3-db104bb6a3f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_019fd756-d25c-75bb-b0de-9d1910282c08" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d25c-7236-a727-5d363364d96d" xlink:to="loc_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners_019fd756-d25c-75bb-b0de-9d1910282c08" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d25c-7413-b532-6bd79c8db859" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfRealEstateProperties"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d25c-7236-a727-5d363364d96d" xlink:to="loc_us-gaap_NumberOfRealEstateProperties_019fd756-d25c-7413-b532-6bd79c8db859" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_019fd756-d25c-7dbf-b6b5-382cbb2166da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d25c-7236-a727-5d363364d96d" xlink:to="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_019fd756-d25c-7dbf-b6b5-382cbb2166da" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_019fd756-d25c-7ddc-81a3-e022f73b4ad7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d25c-7236-a727-5d363364d96d" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_019fd756-d25c-7ddc-81a3-e022f73b4ad7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_019fd756-d25c-7426-846a-8c24c6964f28" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fd756-d25c-7236-a727-5d363364d96d" xlink:to="loc_us-gaap_SaleOfStockPercentageOfOwnershipAfterTransaction_019fd756-d25c-7426-846a-8c24c6964f28" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/SegmentInformationScheduleofSegmentInformationDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#SegmentInformationScheduleofSegmentInformationDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/SegmentInformationScheduleofSegmentInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019fd756-d25c-7fd5-9b1f-8d36ec36f5a0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019fd756-d25c-7384-baeb-3e7819ce3a4d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019fd756-d25c-7fd5-9b1f-8d36ec36f5a0" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019fd756-d25c-7384-baeb-3e7819ce3a4d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_019fd756-d25c-768c-a2e1-5a7ecd908c76" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019fd756-d25c-7384-baeb-3e7819ce3a4d" xlink:to="loc_srt_ConsolidationItemsAxis_019fd756-d25c-768c-a2e1-5a7ecd908c76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019fd756-d25c-768c-a2e1-5a7ecd908c76_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_019fd756-d25c-768c-a2e1-5a7ecd908c76" xlink:to="loc_srt_ConsolidationItemsDomain_019fd756-d25c-768c-a2e1-5a7ecd908c76_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019fd756-d25c-74d1-94a5-c591e8e619ee" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_019fd756-d25c-768c-a2e1-5a7ecd908c76" xlink:to="loc_srt_ConsolidationItemsDomain_019fd756-d25c-74d1-94a5-c591e8e619ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_019fd756-d25c-7622-a22c-e6eb6ec17d7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019fd756-d25c-74d1-94a5-c591e8e619ee" xlink:to="loc_us-gaap_OperatingSegmentsMember_019fd756-d25c-7622-a22c-e6eb6ec17d7c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MaterialReconcilingItemsMember_019fd756-d25c-70b3-9eea-17546222e941" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MaterialReconcilingItemsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019fd756-d25c-74d1-94a5-c591e8e619ee" xlink:to="loc_us-gaap_MaterialReconcilingItemsMember_019fd756-d25c-70b3-9eea-17546222e941" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_019fd756-d25c-7b64-997f-993f77a94107" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019fd756-d25c-74d1-94a5-c591e8e619ee" xlink:to="loc_us-gaap_CorporateNonSegmentMember_019fd756-d25c-7b64-997f-993f77a94107" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019fd756-d25c-79f1-b468-d31ef555f8a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019fd756-d25c-7384-baeb-3e7819ce3a4d" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019fd756-d25c-79f1-b468-d31ef555f8a5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019fd756-d25c-79f1-b468-d31ef555f8a5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019fd756-d25c-79f1-b468-d31ef555f8a5" xlink:to="loc_us-gaap_SegmentDomain_019fd756-d25c-79f1-b468-d31ef555f8a5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019fd756-d25c-7a2d-acc9-64004dc145a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019fd756-d25c-79f1-b468-d31ef555f8a5" xlink:to="loc_us-gaap_SegmentDomain_019fd756-d25c-7a2d-acc9-64004dc145a3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeaseSegmentMember_019fd756-d25c-7c95-b026-b796a24c2e66" xlink:href="svc-20260930.xsd#svc_NetLeaseSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019fd756-d25c-7a2d-acc9-64004dc145a3" xlink:to="loc_svc_NetLeaseSegmentMember_019fd756-d25c-7c95-b026-b796a24c2e66" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_HotelSegmentMember_019fd756-d25c-759f-afd9-b377bbe90d2b" xlink:href="svc-20260930.xsd#svc_HotelSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019fd756-d25c-7a2d-acc9-64004dc145a3" xlink:to="loc_svc_HotelSegmentMember_019fd756-d25c-759f-afd9-b377bbe90d2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019fd756-d25c-7042-b8ce-e8ed77487ce2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019fd756-d25c-7384-baeb-3e7819ce3a4d" xlink:to="loc_srt_ProductOrServiceAxis_019fd756-d25c-7042-b8ce-e8ed77487ce2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019fd756-d25c-7042-b8ce-e8ed77487ce2_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019fd756-d25c-7042-b8ce-e8ed77487ce2" xlink:to="loc_srt_ProductsAndServicesDomain_019fd756-d25c-7042-b8ce-e8ed77487ce2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019fd756-d25c-74bb-be9d-f07bfe9c1dcb" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019fd756-d25c-7042-b8ce-e8ed77487ce2" xlink:to="loc_srt_ProductsAndServicesDomain_019fd756-d25c-74bb-be9d-f07bfe9c1dcb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OccupancyMember_019fd756-d25c-7647-ada8-a80cbe8cdc5f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OccupancyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019fd756-d25c-74bb-be9d-f07bfe9c1dcb" xlink:to="loc_us-gaap_OccupancyMember_019fd756-d25c-7647-ada8-a80cbe8cdc5f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FoodAndBeverageMember_019fd756-d25c-77bc-8d44-c10a1c5d5b32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FoodAndBeverageMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019fd756-d25c-74bb-be9d-f07bfe9c1dcb" xlink:to="loc_us-gaap_FoodAndBeverageMember_019fd756-d25c-77bc-8d44-c10a1c5d5b32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract_019fd756-d25c-7f20-aa9a-cf565e6deeba" 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_SegmentReportingInformationLineItems_019fd756-d25c-7fd5-9b1f-8d36ec36f5a0" xlink:to="loc_us-gaap_RevenuesAbstract_019fd756-d25c-7f20-aa9a-cf565e6deeba" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019fd756-d25c-7299-973e-79b08985c633" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019fd756-d25c-7f20-aa9a-cf565e6deeba" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019fd756-d25c-7299-973e-79b08985c633" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLeaseIncomeLeasePayments_019fd756-d25c-7612-9957-f6ae675a0aaa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLeaseIncomeLeasePayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019fd756-d25c-7f20-aa9a-cf565e6deeba" xlink:to="loc_us-gaap_OperatingLeaseLeaseIncomeLeasePayments_019fd756-d25c-7612-9957-f6ae675a0aaa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_019fd756-d25c-7ba2-935a-2d88294d91b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Revenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_019fd756-d25c-7f20-aa9a-cf565e6deeba" xlink:to="loc_us-gaap_Revenues_019fd756-d25c-7ba2-935a-2d88294d91b6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019fd756-d25c-7fd5-9b1f-8d36ec36f5a0" xlink:to="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019fd756-d25c-7595-9469-ff7b307d5d60" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:to="loc_us-gaap_CostOfGoodsAndServiceExcludingDepreciationDepletionAndAmortization_019fd756-d25c-7595-9469-ff7b307d5d60" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeeExpense_019fd756-d25c-7c2e-a2d7-e2fc7c6124a2" 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_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:to="loc_us-gaap_ManagementFeeExpense_019fd756-d25c-7c2e-a2d7-e2fc7c6124a2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealEstateTaxesAndInsurance_019fd756-d25c-7399-bf2e-e5d67ad2c542" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealEstateTaxesAndInsurance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:to="loc_us-gaap_RealEstateTaxesAndInsurance_019fd756-d25c-7399-bf2e-e5d67ad2c542" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCostAndExpenseOperating_019fd756-d25c-7851-aa40-077029bb46fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCostAndExpenseOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:to="loc_us-gaap_OtherCostAndExpenseOperating_019fd756-d25c-7851-aa40-077029bb46fe" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_019fd756-d25c-7f91-8dd1-4b5c9ffddedd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_019fd756-d25c-7f91-8dd1-4b5c9ffddedd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019fd756-d25c-725c-98c8-0da5a331f178" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019fd756-d25c-725c-98c8-0da5a331f178" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount_019fd756-d25c-7a61-a749-539579a8db35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingOtherItemAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:to="loc_us-gaap_SegmentReportingOtherItemAmount_019fd756-d25c-7a61-a749-539579a8db35" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019fd756-d25c-73ce-9027-cfa3544d4789" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_019fd756-d25c-77d8-a8c1-303185055217" xlink:to="loc_us-gaap_NetIncomeLoss_019fd756-d25c-73ce-9027-cfa3544d4789" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_ReconciliationOfSegmentProfitOrLossAbstract_019fd756-d25c-77db-87e7-e2ae15771cdf" xlink:href="svc-20260930.xsd#svc_ReconciliationOfSegmentProfitOrLossAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019fd756-d25c-7fd5-9b1f-8d36ec36f5a0" xlink:to="loc_svc_ReconciliationOfSegmentProfitOrLossAbstract_019fd756-d25c-77db-87e7-e2ae15771cdf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019fd756-d25c-7c96-bffb-96cf1de5a7b8" 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_svc_ReconciliationOfSegmentProfitOrLossAbstract_019fd756-d25c-77db-87e7-e2ae15771cdf" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019fd756-d25c-7c96-bffb-96cf1de5a7b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_BusinessCombinationAcquisitionRelatedCostsAdjusted_019fd756-d25c-70ce-98ba-33e7c16380c6" xlink:href="svc-20260930.xsd#svc_BusinessCombinationAcquisitionRelatedCostsAdjusted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ReconciliationOfSegmentProfitOrLossAbstract_019fd756-d25c-77db-87e7-e2ae15771cdf" xlink:to="loc_svc_BusinessCombinationAcquisitionRelatedCostsAdjusted_019fd756-d25c-70ce-98ba-33e7c16380c6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndOtherIncome_019fd756-d25c-7654-a05e-36cefaca8562" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestAndOtherIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ReconciliationOfSegmentProfitOrLossAbstract_019fd756-d25c-77db-87e7-e2ae15771cdf" xlink:to="loc_us-gaap_InterestAndOtherIncome_019fd756-d25c-7654-a05e-36cefaca8562" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019fd756-d25c-763d-8102-a9d74399a260" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019fd756-d25c-7355-932d-18691056ecb4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ReconciliationOfSegmentProfitOrLossAbstract_019fd756-d25c-77db-87e7-e2ae15771cdf" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019fd756-d25c-7355-932d-18691056ecb4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019fd756-d25c-7869-809e-635047d1e0dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ReconciliationOfSegmentProfitOrLossAbstract_019fd756-d25c-77db-87e7-e2ae15771cdf" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019fd756-d25c-7869-809e-635047d1e0dc" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019fd756-d25c-7820-b843-7b84a2d18b18" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_svc_ReconciliationOfSegmentProfitOrLossAbstract_019fd756-d25c-77db-87e7-e2ae15771cdf" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019fd756-d25c-7820-b843-7b84a2d18b18" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019fd756-d25c-7844-8522-068c8acdd4e9" 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_SegmentReportingInformationLineItems_019fd756-d25c-7fd5-9b1f-8d36ec36f5a0" xlink:to="loc_us-gaap_Assets_019fd756-d25c-7844-8522-068c8acdd4e9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentExpenditureAdditionToLongLivedAssets_019fd756-d25c-7481-b93b-9c1658ffd501" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentExpenditureAdditionToLongLivedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019fd756-d25c-7fd5-9b1f-8d36ec36f5a0" xlink:to="loc_us-gaap_SegmentExpenditureAdditionToLongLivedAssets_019fd756-d25c-7481-b93b-9c1658ffd501" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/FairValueofAssetsandLiabilitiesScheduleofAssetsCarriedatFairValueCategorizedbyLevelofInputsDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#FairValueofAssetsandLiabilitiesScheduleofAssetsCarriedatFairValueCategorizedbyLevelofInputsDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/FairValueofAssetsandLiabilitiesScheduleofAssetsCarriedatFairValueCategorizedbyLevelofInputsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fd756-d25c-7e24-bc7f-27a19cd4846c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fd756-d25c-70dc-8c37-8776fea0d20e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fd756-d25c-7e24-bc7f-27a19cd4846c" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fd756-d25c-70dc-8c37-8776fea0d20e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d25c-72c0-baf3-33579530e26f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fd756-d25c-70dc-8c37-8776fea0d20e" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d25c-72c0-baf3-33579530e26f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d25c-72c0-baf3-33579530e26f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d25c-72c0-baf3-33579530e26f" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d25c-72c0-baf3-33579530e26f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d25c-7307-ac8b-5cd76adc17f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fd756-d25c-72c0-baf3-33579530e26f" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d25c-7307-ac8b-5cd76adc17f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_019fd756-d25c-7c50-a1f7-8fe58a1087a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fd756-d25c-7307-ac8b-5cd76adc17f6" xlink:to="loc_us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember_019fd756-d25c-7c50-a1f7-8fe58a1087a1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019fd756-d25c-782c-8bdc-f46ee72faaf1" 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_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fd756-d25c-70dc-8c37-8776fea0d20e" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019fd756-d25c-782c-8bdc-f46ee72faaf1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019fd756-d25c-782c-8bdc-f46ee72faaf1_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_019fd756-d25c-782c-8bdc-f46ee72faaf1" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019fd756-d25c-782c-8bdc-f46ee72faaf1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019fd756-d25c-79f1-9cfc-c252068a2b45" 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_019fd756-d25c-782c-8bdc-f46ee72faaf1" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019fd756-d25c-79f1-9cfc-c252068a2b45" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019fd756-d25c-7037-9f2e-3bdc00ffb36a" 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_019fd756-d25c-79f1-9cfc-c252068a2b45" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019fd756-d25c-7037-9f2e-3bdc00ffb36a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019fd756-d25c-7dd3-89a6-947ae0ed1f85" 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_019fd756-d25c-79f1-9cfc-c252068a2b45" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019fd756-d25c-7dd3-89a6-947ae0ed1f85" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019fd756-d25c-7121-90d2-8606702e82ae" 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_019fd756-d25c-79f1-9cfc-c252068a2b45" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019fd756-d25c-7121-90d2-8606702e82ae" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d25c-7f5c-9dfa-6696d32ad5d0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fd756-d25c-70dc-8c37-8776fea0d20e" xlink:to="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d25c-7f5c-9dfa-6696d32ad5d0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-7f5c-9dfa-6696d32ad5d0_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d25c-7f5c-9dfa-6696d32ad5d0" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-7f5c-9dfa-6696d32ad5d0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-716c-ab3a-b0527f208cf7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MortgageLoansOnRealEstateNamePropertyTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis_019fd756-d25c-7f5c-9dfa-6696d32ad5d0" xlink:to="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-716c-ab3a-b0527f208cf7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HotelMember_019fd756-d25c-7bd6-a60f-098cae5e0711" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HotelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-716c-ab3a-b0527f208cf7" xlink:to="loc_srt_HotelMember_019fd756-d25c-7bd6-a60f-098cae5e0711" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeasePropertyMember_019fd756-d25c-7cdd-a7c2-9f4eb845fe22" xlink:href="svc-20260930.xsd#svc_NetLeasePropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_MortgageLoansOnRealEstateNamePropertyTypeDomain_019fd756-d25c-716c-ab3a-b0527f208cf7" xlink:to="loc_svc_NetLeasePropertyMember_019fd756-d25c-7cdd-a7c2-9f4eb845fe22" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d25c-7b58-9a17-1f00692d67f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fd756-d25c-70dc-8c37-8776fea0d20e" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d25c-7b58-9a17-1f00692d67f9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d25c-7b58-9a17-1f00692d67f9_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d25c-7b58-9a17-1f00692d67f9" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d25c-7b58-9a17-1f00692d67f9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d25c-7184-8c4e-811cd25e301f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_019fd756-d25c-7b58-9a17-1f00692d67f9" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d25c-7184-8c4e-811cd25e301f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_RealEstateDispositionsMember_019fd756-d25c-7155-b8c4-140b2248eb67" xlink:href="svc-20260930.xsd#svc_RealEstateDispositionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_019fd756-d25c-7184-8c4e-811cd25e301f" xlink:to="loc_svc_RealEstateDispositionsMember_019fd756-d25c-7155-b8c4-140b2248eb67" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure_019fd756-d25c-78c4-a509-7b2ab304ce19" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fd756-d25c-7e24-bc7f-27a19cd4846c" xlink:to="loc_us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure_019fd756-d25c-78c4-a509-7b2ab304ce19" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NumberOfRealEstatePropertiesSubjectToImpairment_019fd756-d25c-76e2-bce2-e64d0b172442" xlink:href="svc-20260930.xsd#svc_NumberOfRealEstatePropertiesSubjectToImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fd756-d25c-7e24-bc7f-27a19cd4846c" xlink:to="loc_svc_NumberOfRealEstatePropertiesSubjectToImpairment_019fd756-d25c-76e2-bce2-e64d0b172442" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetImpairmentCharges_019fd756-d25c-7390-8e39-f793545d169b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fd756-d25c-7e24-bc7f-27a19cd4846c" xlink:to="loc_us-gaap_AssetImpairmentCharges_019fd756-d25c-7390-8e39-f793545d169b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_019fd756-d25c-72fe-820f-4caad982081d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fd756-d25c-7e24-bc7f-27a19cd4846c" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_019fd756-d25c-72fe-820f-4caad982081d" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.svcreit.com/role/FairValueofAssetsandLiabilitiesScheduleofFairValuesofFinancialInstrumentsDetails" xlink:type="simple" xlink:href="svc-20260930.xsd#FairValueofAssetsandLiabilitiesScheduleofFairValuesofFinancialInstrumentsDetails"/>
  <link:definitionLink xlink:role="http://www.svcreit.com/role/FairValueofAssetsandLiabilitiesScheduleofFairValuesofFinancialInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019fd756-d25c-7ed5-95a9-508bb51f060b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByBalanceSheetGroupingTable_019fd756-d25c-7591-8850-b81c2d822995" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByBalanceSheetGroupingTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019fd756-d25c-7ed5-95a9-508bb51f060b" xlink:to="loc_us-gaap_FairValueByBalanceSheetGroupingTable_019fd756-d25c-7591-8850-b81c2d822995" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019fd756-d25c-774d-bf6f-2afdb55ab0e0" 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_FairValueByBalanceSheetGroupingTable_019fd756-d25c-7591-8850-b81c2d822995" xlink:to="loc_us-gaap_DebtInstrumentAxis_019fd756-d25c-774d-bf6f-2afdb55ab0e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-774d-bf6f-2afdb55ab0e0_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_019fd756-d25c-774d-bf6f-2afdb55ab0e0" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-774d-bf6f-2afdb55ab0e0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" 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_019fd756-d25c-774d-bf6f-2afdb55ab0e0" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes4.95PercentDue2027Member_019fd756-d25c-74e2-9746-eb3185a8b1a3" xlink:href="svc-20260930.xsd#svc_SeniorNotes4.95PercentDue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorNotes4.95PercentDue2027Member_019fd756-d25c-74e2-9746-eb3185a8b1a3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes550PercentDue2027Member_019fd756-d25c-72a8-9478-f711fca7ad07" xlink:href="svc-20260930.xsd#svc_SeniorNotes550PercentDue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorNotes550PercentDue2027Member_019fd756-d25c-72a8-9478-f711fca7ad07" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorSecuredNotesDue2027Member_019fd756-d25c-74d3-95af-490abae9fc6b" xlink:href="svc-20260930.xsd#svc_SeniorSecuredNotesDue2027Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorSecuredNotesDue2027Member_019fd756-d25c-74d3-95af-490abae9fc6b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_019fd756-d25c-7870-b357-602070e18784" xlink:href="svc-20260930.xsd#svc_NetLeaseMortgageNotes5.60PercentDue2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_NetLeaseMortgageNotes5.60PercentDue2028Member_019fd756-d25c-7870-b357-602070e18784" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes3.95PercentDue2028Member_019fd756-d25c-7d4f-a980-605179ffcde6" xlink:href="svc-20260930.xsd#svc_SeniorNotes3.95PercentDue2028Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorNotes3.95PercentDue2028Member_019fd756-d25c-7d4f-a980-605179ffcde6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes8.375PercentDue2029Member_019fd756-d25c-7641-8b87-7a43f8be179f" xlink:href="svc-20260930.xsd#svc_SeniorNotes8.375PercentDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorNotes8.375PercentDue2029Member_019fd756-d25c-7641-8b87-7a43f8be179f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes4.95PercentDue2029Member_019fd756-d25c-7dbf-9c3f-5d5853aabdbc" xlink:href="svc-20260930.xsd#svc_SeniorNotes4.95PercentDue2029Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorNotes4.95PercentDue2029Member_019fd756-d25c-7dbf-9c3f-5d5853aabdbc" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes4375PercentDue2030Member_019fd756-d25c-7a00-b924-a6afe14d5328" xlink:href="svc-20260930.xsd#svc_SeniorNotes4375PercentDue2030Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorNotes4375PercentDue2030Member_019fd756-d25c-7a00-b924-a6afe14d5328" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_019fd756-d25c-733e-a884-c31204a38ced" xlink:href="svc-20260930.xsd#svc_NetLeaseMortgageNotes5.96PercentDue2031Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_NetLeaseMortgageNotes5.96PercentDue2031Member_019fd756-d25c-733e-a884-c31204a38ced" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes8.625PercentDue2031Member_019fd756-d25c-747f-90da-6d4137f85081" xlink:href="svc-20260930.xsd#svc_SeniorNotes8.625PercentDue2031Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorNotes8.625PercentDue2031Member_019fd756-d25c-747f-90da-6d4137f85081" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_svc_SeniorNotes8.875PercentDue2032Member_019fd756-d25c-7d98-85f5-486d3a66010f" xlink:href="svc-20260930.xsd#svc_SeniorNotes8.875PercentDue2032Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019fd756-d25c-7bc8-ad4b-317011145594" xlink:to="loc_svc_SeniorNotes8.875PercentDue2032Member_019fd756-d25c-7d98-85f5-486d3a66010f" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_019fd756-d25c-7fee-96db-b6b7ece796f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_019fd756-d25c-7591-8850-b81c2d822995" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_019fd756-d25c-7fee-96db-b6b7ece796f7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019fd756-d25c-7fee-96db-b6b7ece796f7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019fd756-d25c-7fee-96db-b6b7ece796f7" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019fd756-d25c-7fee-96db-b6b7ece796f7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019fd756-d25c-7f1b-8963-f7e39e8e009d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019fd756-d25c-7fee-96db-b6b7ece796f7" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019fd756-d25c-7f1b-8963-f7e39e8e009d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019fd756-d25c-7ece-98db-2b677bfc6b92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019fd756-d25c-7f1b-8963-f7e39e8e009d" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019fd756-d25c-7ece-98db-2b677bfc6b92" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_019fd756-d25c-71fa-8b85-4dd5b333d3ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019fd756-d25c-7ece-98db-2b677bfc6b92" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_019fd756-d25c-71fa-8b85-4dd5b333d3ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019fd756-d25c-768f-81c0-687830f29406" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019fd756-d25c-7ece-98db-2b677bfc6b92" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019fd756-d25c-768f-81c0-687830f29406" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_019fd756-d25c-77d4-a0a8-78db7b30fe8c" 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_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019fd756-d25c-7ed5-95a9-508bb51f060b" xlink:to="loc_us-gaap_LongTermDebtFairValue_019fd756-d25c-77d4-a0a8-78db7b30fe8c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019fd756-d25c-7e69-874a-b519c66bc19c" 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_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_019fd756-d25c-7ed5-95a9-508bb51f060b" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019fd756-d25c-7e69-874a-b519c66bc19c" xlink:type="arc" order="1"/>
  </link:definitionLink>
</link:linkbase>
