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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:01a05da9-2295-7bf1-84bb-b431a1ec5501,g:532a6c54-a63a-4394-afb4-08b5361c1132-->
<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.greenlightre.ky/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINSHAREHOLDERSEQUITY" xlink:type="simple" xlink:href="glre-20260930.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINSHAREHOLDERSEQUITY"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINSHAREHOLDERSEQUITY" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_01a05da9-23c9-75ef-86e5-e95e78cd3cdc" 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_01a05da9-23c9-74fc-8c32-c6cfd8737627" 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_01a05da9-23c9-75ef-86e5-e95e78cd3cdc" xlink:to="loc_us-gaap_StatementTable_01a05da9-23c9-74fc-8c32-c6cfd8737627" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_01a05da9-23c9-76ce-b3ed-6b7e0ee056e6" 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_01a05da9-23c9-74fc-8c32-c6cfd8737627" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_01a05da9-23c9-76ce-b3ed-6b7e0ee056e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a05da9-23c9-76ce-b3ed-6b7e0ee056e6_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_01a05da9-23c9-76ce-b3ed-6b7e0ee056e6" xlink:to="loc_us-gaap_EquityComponentDomain_01a05da9-23c9-76ce-b3ed-6b7e0ee056e6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_01a05da9-23c9-71c5-8f3c-42721b2068af" 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_01a05da9-23c9-76ce-b3ed-6b7e0ee056e6" xlink:to="loc_us-gaap_EquityComponentDomain_01a05da9-23c9-71c5-8f3c-42721b2068af" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_01a05da9-23c9-7cfc-a8f5-43b96c557c9e" 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_01a05da9-23c9-71c5-8f3c-42721b2068af" xlink:to="loc_us-gaap_CommonStockMember_01a05da9-23c9-7cfc-a8f5-43b96c557c9e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_01a05da9-23c9-7f64-86f1-30cfa727a1b1" 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_01a05da9-23c9-71c5-8f3c-42721b2068af" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_01a05da9-23c9-7f64-86f1-30cfa727a1b1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_01a05da9-23c9-79f8-a449-32602c22b69e" 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_01a05da9-23c9-71c5-8f3c-42721b2068af" xlink:to="loc_us-gaap_RetainedEarningsMember_01a05da9-23c9-79f8-a449-32602c22b69e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a05da9-23c9-7746-9b52-f38ea9c33295" 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_01a05da9-23c9-75ef-86e5-e95e78cd3cdc" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a05da9-23c9-7746-9b52-f38ea9c33295" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_01a05da9-23c9-764b-a336-8a19c8eef6a7" 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_01a05da9-23c9-7746-9b52-f38ea9c33295" xlink:to="loc_us-gaap_StockholdersEquity_01a05da9-23c9-764b-a336-8a19c8eef6a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensationForfeited_01a05da9-23c9-77d1-930a-9490a9ef2351" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensationForfeited"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a05da9-23c9-7746-9b52-f38ea9c33295" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensationForfeited_01a05da9-23c9-77d1-930a-9490a9ef2351" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_01a05da9-23c9-7d57-bb83-0c94e6a9be3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a05da9-23c9-7746-9b52-f38ea9c33295" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_01a05da9-23c9-7d57-bb83-0c94e6a9be3b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_01a05da9-23c9-7539-9eb5-2fc3882618c4" 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_01a05da9-23c9-7746-9b52-f38ea9c33295" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_01a05da9-23c9-7539-9eb5-2fc3882618c4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_01a05da9-23c9-7751-b1bc-50a26b94e8e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_01a05da9-23c9-7746-9b52-f38ea9c33295" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_01a05da9-23c9-7751-b1bc-50a26b94e8e0" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_01a05da9-23c9-780f-9c53-68e8b285b283" 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_01a05da9-23c9-7746-9b52-f38ea9c33295" xlink:to="loc_us-gaap_NetIncomeLoss_01a05da9-23c9-780f-9c53-68e8b285b283" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_01a05da9-23c9-7b35-9c80-ff27eadf5b76" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/ORGANIZATIONANDBASISOFPRESENTATIONDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#ORGANIZATIONANDBASISOFPRESENTATIONDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/ORGANIZATIONANDBASISOFPRESENTATIONDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_01a1762d-786f-759f-bd10-365aca6d8bcf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_01a1762d-786f-704c-a019-edfe9225552d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_01a1762d-786f-759f-bd10-365aca6d8bcf" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_01a1762d-786f-704c-a019-edfe9225552d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementAxis_01a1762d-ef87-75d4-aa33-4bff2cde4862" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RestatementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_01a1762d-786f-704c-a019-edfe9225552d" xlink:to="loc_srt_RestatementAxis_01a1762d-ef87-75d4-aa33-4bff2cde4862" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_01a1762d-ef87-75d4-aa33-4bff2cde4862_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RestatementAxis_01a1762d-ef87-75d4-aa33-4bff2cde4862" xlink:to="loc_srt_RestatementDomain_01a1762d-ef87-75d4-aa33-4bff2cde4862_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_01a1762d-ef87-7f71-a643-a70eb5e053a8" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RestatementAxis_01a1762d-ef87-75d4-aa33-4bff2cde4862" xlink:to="loc_srt_RestatementDomain_01a1762d-ef87-7f71-a643-a70eb5e053a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementAdjustmentMember_01a1762e-2920-79cc-8a33-b68d632e5c47" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RestatementAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RestatementDomain_01a1762d-ef87-7f71-a643-a70eb5e053a8" xlink:to="loc_srt_RestatementAdjustmentMember_01a1762e-2920-79cc-8a33-b68d632e5c47" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherUnderwritingExpense_01a1762d-786f-7bc7-8c80-d7e2a658f7ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherUnderwritingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_01a1762d-786f-759f-bd10-365aca6d8bcf" xlink:to="loc_us-gaap_OtherUnderwritingExpense_01a1762d-786f-7bc7-8c80-d7e2a658f7ed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_01a188b3-2c5d-732c-a685-9f67faae26aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationAcquisitionRelatedCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_01a1762d-786f-759f-bd10-365aca6d8bcf" xlink:to="loc_us-gaap_BusinessCombinationAcquisitionRelatedCosts_01a188b3-2c5d-732c-a685-9f67faae26aa" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/INVESTMENTINRELATEDPARTYINVESTMENTFUNDNarrativeDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#INVESTMENTINRELATEDPARTYINVESTMENTFUNDNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/INVESTMENTINRELATEDPARTYINVESTMENTFUNDNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-7611-8bcd-7018243b322f" 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_01a05da9-23c9-705b-a0c2-8633119b36d7" 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_01a05da9-23c9-7611-8bcd-7018243b322f" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a05da9-23c9-705b-a0c2-8633119b36d7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a05da9-23c9-750f-a2af-aaa8f0002514" 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_01a05da9-23c9-705b-a0c2-8633119b36d7" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_01a05da9-23c9-750f-a2af-aaa8f0002514" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a05da9-23c9-750f-a2af-aaa8f0002514_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_01a05da9-23c9-750f-a2af-aaa8f0002514" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a05da9-23c9-750f-a2af-aaa8f0002514_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_01a05da9-23c9-72e7-aaf6-ed5e8e4dc70e" 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_01a05da9-23c9-750f-a2af-aaa8f0002514" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_01a05da9-23c9-72e7-aaf6-ed5e8e4dc70e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-23c9-7d9e-b1bd-67d60442652f" xlink:href="glre-20260930.xsd#glre_SolasglasInvestmentsLPSILPMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a05da9-23c9-72e7-aaf6-ed5e8e4dc70e" xlink:to="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-23c9-7d9e-b1bd-67d60442652f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_SILPGeneralPartnerMember_01a05da9-23c9-75b5-8c6b-459204b6ba2b" xlink:href="glre-20260930.xsd#glre_SILPGeneralPartnerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_01a05da9-23c9-72e7-aaf6-ed5e8e4dc70e" xlink:to="loc_glre_SILPGeneralPartnerMember_01a05da9-23c9-75b5-8c6b-459204b6ba2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_01a05da9-23c9-7270-87ee-4cee3c928b93" 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_ScheduleOfEquityMethodInvestmentsTable_01a05da9-23c9-705b-a0c2-8633119b36d7" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_01a05da9-23c9-7270-87ee-4cee3c928b93" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_01a05da9-23c9-7270-87ee-4cee3c928b93_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_01a05da9-23c9-7270-87ee-4cee3c928b93" xlink:to="loc_us-gaap_RelatedPartyDomain_01a05da9-23c9-7270-87ee-4cee3c928b93_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_01a05da9-23c9-7322-8689-76aa4f9e2539" 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_01a05da9-23c9-7270-87ee-4cee3c928b93" xlink:to="loc_us-gaap_RelatedPartyDomain_01a05da9-23c9-7322-8689-76aa4f9e2539" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_GreenlightCapitalReLimitedPartnersMember_01a05da9-23c9-78c2-a459-9660f39cdd21" xlink:href="glre-20260930.xsd#glre_GreenlightCapitalReLimitedPartnersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_01a05da9-23c9-7322-8689-76aa4f9e2539" xlink:to="loc_glre_GreenlightCapitalReLimitedPartnersMember_01a05da9-23c9-78c2-a459-9660f39cdd21" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentsFairValueDisclosure_01a05da9-23c9-73eb-b32f-f6793927e644" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-7611-8bcd-7018243b322f" xlink:to="loc_us-gaap_EquityMethodInvestmentsFairValueDisclosure_01a05da9-23c9-73eb-b32f-f6793927e644" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_01a05da9-23c9-70bd-aabd-8eac8468623b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-7611-8bcd-7018243b322f" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_01a05da9-23c9-70bd-aabd-8eac8468623b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_01a05da9-23c9-7d8b-80a3-adc28d551334" 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_01a05da9-23c9-7611-8bcd-7018243b322f" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_01a05da9-23c9-7d8b-80a3-adc28d551334" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/INVESTMENTINRELATEDPARTYINVESTMENTFUNDScheduleofFinancialInformationofInvestmentDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#INVESTMENTINRELATEDPARTYINVESTMENTFUNDScheduleofFinancialInformationofInvestmentDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/INVESTMENTINRELATEDPARTYINVESTMENTFUNDScheduleofFinancialInformationofInvestmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-7335-97c9-b811514416c2" 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_01a05da9-23c9-705c-96ef-664cd75e29d4" 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_01a05da9-23c9-7335-97c9-b811514416c2" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a05da9-23c9-705c-96ef-664cd75e29d4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_01a05da9-23c9-7150-ad9c-b5d2b2e52d17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a05da9-23c9-705c-96ef-664cd75e29d4" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_01a05da9-23c9-7150-ad9c-b5d2b2e52d17" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-7150-ad9c-b5d2b2e52d17_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_01a05da9-23c9-7150-ad9c-b5d2b2e52d17" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-7150-ad9c-b5d2b2e52d17_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-7412-80dc-a9a8faf6aa19" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_01a05da9-23c9-7150-ad9c-b5d2b2e52d17" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-7412-80dc-a9a8faf6aa19" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-23c9-70a3-9c42-0087c1da8528" xlink:href="glre-20260930.xsd#glre_SolasglasInvestmentsLPSILPMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-7412-80dc-a9a8faf6aa19" xlink:to="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-23c9-70a3-9c42-0087c1da8528" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a05da9-23c9-7665-b404-0928b8a00d19" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-7335-97c9-b811514416c2" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a05da9-23c9-7665-b404-0928b8a00d19" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_01a05da9-23c9-7a60-8894-cd01648c4772" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a05da9-23c9-7665-b404-0928b8a00d19" xlink:to="loc_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_01a05da9-23c9-7a60-8894-cd01648c4772" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_01a05da9-23c9-7992-95b6-182e57a885c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a05da9-23c9-7665-b404-0928b8a00d19" xlink:to="loc_us-gaap_DerivativeAssets_01a05da9-23c9-7992-95b6-182e57a885c1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DueFromCorrespondentBrokers_01a05da9-23c9-74cd-bd23-791d96d93bab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DueFromCorrespondentBrokers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a05da9-23c9-7665-b404-0928b8a00d19" xlink:to="loc_us-gaap_DueFromCorrespondentBrokers_01a05da9-23c9-74cd-bd23-791d96d93bab" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendAndInterestReceivable_01a05da9-23c9-784a-8bce-da7e8677b538" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendAndInterestReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_01a05da9-23c9-7665-b404-0928b8a00d19" xlink:to="loc_us-gaap_DividendAndInterestReceivable_01a05da9-23c9-784a-8bce-da7e8677b538" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_01a05da9-23c9-7727-99dd-43ca04d303d8" 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_AssetsFairValueDisclosureAbstract_01a05da9-23c9-7665-b404-0928b8a00d19" xlink:to="loc_us-gaap_Assets_01a05da9-23c9-7727-99dd-43ca04d303d8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a05da9-23c9-7115-939a-de223580d639" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-7335-97c9-b811514416c2" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a05da9-23c9-7115-939a-de223580d639" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsSoldNotYetPurchasedAtFairValue_01a05da9-23c9-715e-bd25-c950e08af701" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsSoldNotYetPurchasedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a05da9-23c9-7115-939a-de223580d639" xlink:to="loc_us-gaap_FinancialInstrumentsSoldNotYetPurchasedAtFairValue_01a05da9-23c9-715e-bd25-c950e08af701" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_01a05da9-23c9-78d5-b176-ca08c0dc6946" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a05da9-23c9-7115-939a-de223580d639" xlink:to="loc_us-gaap_DerivativeLiabilities_01a05da9-23c9-78d5-b176-ca08c0dc6946" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CapitalWithdrawalsPayable_01a05da9-23c9-774b-a292-cc769172b74c" xlink:href="glre-20260930.xsd#glre_CapitalWithdrawalsPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a05da9-23c9-7115-939a-de223580d639" xlink:to="loc_glre_CapitalWithdrawalsPayable_01a05da9-23c9-774b-a292-cc769172b74c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendsPayableCurrentAndNoncurrent_01a05da9-23c9-7d7c-8993-fec9e960ceb3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestAndDividendsPayableCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_01a05da9-23c9-7115-939a-de223580d639" xlink:to="loc_us-gaap_InterestAndDividendsPayableCurrentAndNoncurrent_01a05da9-23c9-7d7c-8993-fec9e960ceb3" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilities_01a05da9-23c9-75e0-b637-21e8639a49b6" 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_LiabilitiesFairValueDisclosureAbstract_01a05da9-23c9-7115-939a-de223580d639" xlink:to="loc_us-gaap_OtherLiabilities_01a05da9-23c9-75e0-b637-21e8639a49b6" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_01a05da9-23c9-7f6c-8fbb-df07175ca405" 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_LiabilitiesFairValueDisclosureAbstract_01a05da9-23c9-7115-939a-de223580d639" xlink:to="loc_us-gaap_Liabilities_01a05da9-23c9-7f6c-8fbb-df07175ca405" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsNet_01a05da9-23c9-7cb9-b771-8faad492d0c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-7335-97c9-b811514416c2" xlink:to="loc_us-gaap_AssetsNet_01a05da9-23c9-7cb9-b771-8faad492d0c4" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/INVESTMENTINRELATEDPARTYINVESTMENTFUNDScheduleofSummarizedStatementsofAssetsLiabilitiesandNetAssetsofSILPDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#INVESTMENTINRELATEDPARTYINVESTMENTFUNDScheduleofSummarizedStatementsofAssetsLiabilitiesandNetAssetsofSILPDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/INVESTMENTINRELATEDPARTYINVESTMENTFUNDScheduleofSummarizedStatementsofAssetsLiabilitiesandNetAssetsofSILPDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" 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_01a05da9-23c9-799f-889a-1096889667d4" 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_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a05da9-23c9-799f-889a-1096889667d4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_01a05da9-23c9-7e95-84ac-094f169f8cec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a05da9-23c9-799f-889a-1096889667d4" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_01a05da9-23c9-7e95-84ac-094f169f8cec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-7e95-84ac-094f169f8cec_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_01a05da9-23c9-7e95-84ac-094f169f8cec" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-7e95-84ac-094f169f8cec_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-78be-a247-58900af2a599" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_01a05da9-23c9-7e95-84ac-094f169f8cec" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-78be-a247-58900af2a599" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-23c9-78f3-bf2e-945bde5e2006" xlink:href="glre-20260930.xsd#glre_SolasglasInvestmentsLPSILPMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_01a05da9-23c9-78be-a247-58900af2a599" xlink:to="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-23c9-78f3-bf2e-945bde5e2006" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a05da9-23c9-73df-94b9-9dc7061cb87d" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_01a05da9-23c9-799f-889a-1096889667d4" xlink:to="loc_dei_LegalEntityAxis_01a05da9-23c9-73df-94b9-9dc7061cb87d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a05da9-23c9-73df-94b9-9dc7061cb87d_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a05da9-23c9-73df-94b9-9dc7061cb87d" xlink:to="loc_dei_EntityDomain_01a05da9-23c9-73df-94b9-9dc7061cb87d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a05da9-23c9-7e60-a005-fa927c4b7b25" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a05da9-23c9-73df-94b9-9dc7061cb87d" xlink:to="loc_dei_EntityDomain_01a05da9-23c9-7e60-a005-fa927c4b7b25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-23c9-7471-966a-be86ed98a9f5" xlink:href="glre-20260930.xsd#glre_SolasglasInvestmentsLPSILPMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a05da9-23c9-7e60-a005-fa927c4b7b25" xlink:to="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-23c9-7471-966a-be86ed98a9f5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationInvestmentIncomeAbstract_01a05da9-23c9-77f2-ae14-085d4674c089" xlink:href="glre-20260930.xsd#glre_EquityMethodInvestmentSummarizedFinancialInformationInvestmentIncomeAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationInvestmentIncomeAbstract_01a05da9-23c9-77f2-ae14-085d4674c089" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendIncomeOperating_01a05da9-23c9-7bd3-bc33-feabd6f86c7d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationInvestmentIncomeAbstract_01a05da9-23c9-77f2-ae14-085d4674c089" xlink:to="loc_us-gaap_DividendIncomeOperating_01a05da9-23c9-7bd3-bc33-feabd6f86c7d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInterest_01a05da9-23c9-7f20-8330-1ba4077e550a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationInvestmentIncomeAbstract_01a05da9-23c9-77f2-ae14-085d4674c089" xlink:to="loc_us-gaap_InvestmentIncomeInterest_01a05da9-23c9-7f20-8330-1ba4077e550a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperating_01a05da9-23c9-73af-bb4d-834abaf89e0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestAndDividendIncomeOperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationInvestmentIncomeAbstract_01a05da9-23c9-77f2-ae14-085d4674c089" xlink:to="loc_us-gaap_InterestAndDividendIncomeOperating_01a05da9-23c9-73af-bb4d-834abaf89e0a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_EquityMethodInvestmentsSummarizedFinancialInformationExpensesAbstract_01a05da9-23c9-7736-bee8-8fc7f2319482" xlink:href="glre-20260930.xsd#glre_EquityMethodInvestmentsSummarizedFinancialInformationExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_glre_EquityMethodInvestmentsSummarizedFinancialInformationExpensesAbstract_01a05da9-23c9-7736-bee8-8fc7f2319482" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeeExpense_01a05da9-23c9-7a04-bcb5-2940a935fac4" 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_glre_EquityMethodInvestmentsSummarizedFinancialInformationExpensesAbstract_01a05da9-23c9-7736-bee8-8fc7f2319482" xlink:to="loc_us-gaap_ManagementFeeExpense_01a05da9-23c9-7a04-bcb5-2940a935fac4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOther_01a05da9-23c9-7659-81b3-4fa54bea0c86" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentsSummarizedFinancialInformationExpensesAbstract_01a05da9-23c9-7736-bee8-8fc7f2319482" xlink:to="loc_us-gaap_InterestExpenseOther_01a05da9-23c9-7659-81b3-4fa54bea0c86" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_DividendExpense_01a05da9-23c9-7677-b9ae-98eb6845679e" xlink:href="glre-20260930.xsd#glre_DividendExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentsSummarizedFinancialInformationExpensesAbstract_01a05da9-23c9-7736-bee8-8fc7f2319482" xlink:to="loc_glre_DividendExpense_01a05da9-23c9-7677-b9ae-98eb6845679e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ResearchAndOperatingExpense_01a05da9-23c9-7139-add6-6876045fa88f" xlink:href="glre-20260930.xsd#glre_ResearchAndOperatingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentsSummarizedFinancialInformationExpensesAbstract_01a05da9-23c9-7736-bee8-8fc7f2319482" xlink:to="loc_glre_ResearchAndOperatingExpense_01a05da9-23c9-7139-add6-6876045fa88f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BenefitsLossesAndExpenses_01a05da9-23c9-7119-8636-4c1219ca0e3f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BenefitsLossesAndExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentsSummarizedFinancialInformationExpensesAbstract_01a05da9-23c9-7736-bee8-8fc7f2319482" xlink:to="loc_us-gaap_BenefitsLossesAndExpenses_01a05da9-23c9-7119-8636-4c1219ca0e3f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_InvestmentIncome_01a05da9-23c9-728b-be25-0b09cbc35a9f" xlink:href="glre-20260930.xsd#glre_InvestmentIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_glre_InvestmentIncome_01a05da9-23c9-728b-be25-0b09cbc35a9f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationGainLossOnInvestmentAbstract_01a05da9-23c9-78ff-b246-285cb6987b86" xlink:href="glre-20260930.xsd#glre_EquityMethodInvestmentSummarizedFinancialInformationGainLossOnInvestmentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationGainLossOnInvestmentAbstract_01a05da9-23c9-78ff-b246-285cb6987b86" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RealizedInvestmentGainsLosses_01a05da9-23c9-780c-b4d7-6848182edd45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RealizedInvestmentGainsLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationGainLossOnInvestmentAbstract_01a05da9-23c9-78ff-b246-285cb6987b86" xlink:to="loc_us-gaap_RealizedInvestmentGainsLosses_01a05da9-23c9-780c-b4d7-6848182edd45" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_01a05da9-23c9-7069-bdda-ea73b97f0b20" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationGainLossOnInvestmentAbstract_01a05da9-23c9-78ff-b246-285cb6987b86" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_01a05da9-23c9-7069-bdda-ea73b97f0b20" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnInvestments_01a05da9-23c9-745a-8033-5e5f51682524" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationGainLossOnInvestmentAbstract_01a05da9-23c9-78ff-b246-285cb6987b86" xlink:to="loc_us-gaap_GainLossOnInvestments_01a05da9-23c9-745a-8033-5e5f51682524" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_01a05da9-23c9-720d-b73c-3967f5b86b7e" 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_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_us-gaap_NetIncomeLoss_01a05da9-23c9-720d-b73c-3967f5b86b7e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_01a05da9-23c9-7f26-b50e-b8590c101a20" 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_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_01a05da9-23c9-7f26-b50e-b8590c101a20" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationManagementFeeExpense_01a05da9-23c9-775d-a6bf-35e2ea4fb999" xlink:href="glre-20260930.xsd#glre_EquityMethodInvestmentSummarizedFinancialInformationManagementFeeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_glre_EquityMethodInvestmentSummarizedFinancialInformationManagementFeeExpense_01a05da9-23c9-775d-a6bf-35e2ea4fb999" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_IncentiveFeeAdjustment_01a05da9-23c9-7cc6-ab67-3eca1f308fe9" xlink:href="glre-20260930.xsd#glre_IncentiveFeeAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_glre_IncentiveFeeAdjustment_01a05da9-23c9-7cc6-ab67-3eca1f308fe9" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_TotalExpense_01a05da9-23c9-7640-8c30-ec6efd517779" xlink:href="glre-20260930.xsd#glre_TotalExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_01a05da9-23c9-742a-92eb-62e325a66ec5" xlink:to="loc_glre_TotalExpense_01a05da9-23c9-7640-8c30-ec6efd517779" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/FIXEDMATURITYINVESTMENTSDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#FIXEDMATURITYINVESTMENTSDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/FIXEDMATURITYINVESTMENTSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_01a05da9-23c9-71f6-a44b-326de1649b1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable_01a05da9-23c9-742c-89d1-1ba802eb8d5d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_01a05da9-23c9-71f6-a44b-326de1649b1f" xlink:to="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable_01a05da9-23c9-742c-89d1-1ba802eb8d5d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_01a05da9-23c9-7563-9a0f-1e45fcb03d4a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable_01a05da9-23c9-742c-89d1-1ba802eb8d5d" xlink:to="loc_us-gaap_FinancialInstrumentAxis_01a05da9-23c9-7563-9a0f-1e45fcb03d4a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7563-9a0f-1e45fcb03d4a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01a05da9-23c9-7563-9a0f-1e45fcb03d4a" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7563-9a0f-1e45fcb03d4a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-773d-8db9-0e4670e9b970" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01a05da9-23c9-7563-9a0f-1e45fcb03d4a" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-773d-8db9-0e4670e9b970" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_01a05da9-23c9-7c83-ab31-bfc84e5257a0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-773d-8db9-0e4670e9b970" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_01a05da9-23c9-7c83-ab31-bfc84e5257a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_01a05da9-23c9-771f-b25b-3c16a785ea4d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-773d-8db9-0e4670e9b970" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_01a05da9-23c9-771f-b25b-3c16a785ea4d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateBondSecuritiesMember_01a05da9-23c9-7c48-ab0c-1d33e86c2979" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateBondSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-773d-8db9-0e4670e9b970" xlink:to="loc_us-gaap_CorporateBondSecuritiesMember_01a05da9-23c9-7c48-ab0c-1d33e86c2979" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_01a05da9-23c9-7a8a-a79b-9b3e162f9b94" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-773d-8db9-0e4670e9b970" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_01a05da9-23c9-7a8a-a79b-9b3e162f9b94" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_NonAgencyResidentialMortgageBackedSecuritiesMember_01a05da9-23c9-765c-bc1c-d4d881f08188" xlink:href="glre-20260930.xsd#glre_NonAgencyResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-773d-8db9-0e4670e9b970" xlink:to="loc_glre_NonAgencyResidentialMortgageBackedSecuritiesMember_01a05da9-23c9-765c-bc1c-d4d881f08188" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MunicipalBondsMember_01a05da9-23c9-7d97-b2d6-d6721413b990" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MunicipalBondsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-773d-8db9-0e4670e9b970" xlink:to="loc_us-gaap_MunicipalBondsMember_01a05da9-23c9-7d97-b2d6-d6721413b990" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesTradingRestricted_01a05da9-23c9-7a64-b8d4-2d4f85958634" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesTradingRestricted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_01a05da9-23c9-71f6-a44b-326de1649b1f" xlink:to="loc_us-gaap_DebtSecuritiesTradingRestricted_01a05da9-23c9-7a64-b8d4-2d4f85958634" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_LiquidityFundFairValue_01a05da9-23c9-7df5-b612-bd7b76aa6e2a" xlink:href="glre-20260930.xsd#glre_LiquidityFundFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_01a05da9-23c9-71f6-a44b-326de1649b1f" xlink:to="loc_glre_LiquidityFundFairValue_01a05da9-23c9-7df5-b612-bd7b76aa6e2a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecuritiesDebt_01a05da9-23c9-7b1e-bb0f-2665ae2e5074" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_01a05da9-23c9-71f6-a44b-326de1649b1f" xlink:to="loc_us-gaap_TradingSecuritiesDebt_01a05da9-23c9-7b1e-bb0f-2665ae2e5074" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/OTHERINVESTMENTSScheduleofOtherInvestmentsDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#OTHERINVESTMENTSScheduleofOtherInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/OTHERINVESTMENTSScheduleofOtherInvestmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable_01a05da9-23c9-7214-ae61-dc3e405d22b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable_01a05da9-23c9-7214-ae61-dc3e405d22b9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_01a05da9-23c9-7b50-ad2b-20302e684899" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsTable_01a05da9-23c9-7214-ae61-dc3e405d22b9" xlink:to="loc_us-gaap_InvestmentTypeAxis_01a05da9-23c9-7b50-ad2b-20302e684899" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7b50-ad2b-20302e684899_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_01a05da9-23c9-7b50-ad2b-20302e684899" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7b50-ad2b-20302e684899_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7266-828a-7da6c0ab865d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_01a05da9-23c9-7b50-ad2b-20302e684899" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7266-828a-7da6c0ab865d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrivateEquityFundsMember_01a05da9-23c9-7e6c-a4ef-1d257c9a71e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrivateEquityFundsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7266-828a-7da6c0ab865d" xlink:to="loc_us-gaap_PrivateEquityFundsMember_01a05da9-23c9-7e6c-a4ef-1d257c9a71e2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_PrivateConvertibleDebtSecuritiesMember_01a05da9-23c9-7664-8644-02d9e49c42f6" xlink:href="glre-20260930.xsd#glre_PrivateConvertibleDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7266-828a-7da6c0ab865d" xlink:to="loc_glre_PrivateConvertibleDebtSecuritiesMember_01a05da9-23c9-7664-8644-02d9e49c42f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNiCost_01a05da9-23c9-77a9-be4e-15536f231191" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNiCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_EquitySecuritiesFvNiCost_01a05da9-23c9-77a9-be4e-15536f231191" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNiUnrealizedGain_01a05da9-23c9-7b37-984d-29f15a320514" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNiUnrealizedGain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_EquitySecuritiesFvNiUnrealizedGain_01a05da9-23c9-7b37-984d-29f15a320514" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNiUnrealizedLoss_01a05da9-23c9-79ba-9d34-81996b3e7f2f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNiUnrealizedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_EquitySecuritiesFvNiUnrealizedLoss_01a05da9-23c9-79ba-9d34-81996b3e7f2f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestReceivable_01a05da9-23c9-784f-bf50-84a61512c8e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_InterestReceivable_01a05da9-23c9-784f-bf50-84a61512c8e4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNiCurrentAndNoncurrent_01a05da9-23c9-7d32-bd94-1751c3563152" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNiCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_EquitySecuritiesFvNiCurrentAndNoncurrent_01a05da9-23c9-7d32-bd94-1751c3563152" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecuritiesDebtAmortizedCost_01a05da9-23c9-7780-9390-3adcb5f3ac22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingSecuritiesDebtAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_TradingSecuritiesDebtAmortizedCost_01a05da9-23c9-7780-9390-3adcb5f3ac22" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesTradingUnrealizedGain_01a05da9-23c9-7928-945f-abca58d44a4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesTradingUnrealizedGain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_DebtSecuritiesTradingUnrealizedGain_01a05da9-23c9-7928-945f-abca58d44a4e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesTradingUnrealizedLoss_01a05da9-23c9-72b5-b6c6-61e4a76f4c7d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesTradingUnrealizedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_DebtSecuritiesTradingUnrealizedLoss_01a05da9-23c9-72b5-b6c6-61e4a76f4c7d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecuritiesDebt_01a05da9-23c9-799a-bfa2-46aab8bc8738" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_us-gaap_TradingSecuritiesDebt_01a05da9-23c9-799a-bfa2-46aab8bc8738" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OtherInvestmentsCost_01a05da9-23c9-7dc2-a0c0-0ce231b1a04e" xlink:href="glre-20260930.xsd#glre_OtherInvestmentsCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_glre_OtherInvestmentsCost_01a05da9-23c9-7dc2-a0c0-0ce231b1a04e" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OtherInvestmentsUnrealizedGain_01a05da9-23c9-7903-9a93-898490538354" xlink:href="glre-20260930.xsd#glre_OtherInvestmentsUnrealizedGain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_glre_OtherInvestmentsUnrealizedGain_01a05da9-23c9-7903-9a93-898490538354" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OtherInvestmentsUnrealizedLoss_01a05da9-23c9-76c1-88a8-d378a8f9f4e6" xlink:href="glre-20260930.xsd#glre_OtherInvestmentsUnrealizedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_glre_OtherInvestmentsUnrealizedLoss_01a05da9-23c9-76c1-88a8-d378a8f9f4e6" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OtherSecuritiesInvestments_01a05da9-23c9-7a28-be80-6d9806154cb2" xlink:href="glre-20260930.xsd#glre_OtherSecuritiesInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems_01a05da9-23c9-7228-a93f-42c4207386ca" xlink:to="loc_glre_OtherSecuritiesInvestments_01a05da9-23c9-7a28-be80-6d9806154cb2" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/RESTRICTEDCASHANDCASHEQUIVALENTSDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#RESTRICTEDCASHANDCASHEQUIVALENTSDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/RESTRICTEDCASHANDCASHEQUIVALENTSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_01a05da9-23c9-7b62-a83e-6fe5cacd0063" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable_01a05da9-23c9-710d-83fc-09c16416c4bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_01a05da9-23c9-7b62-a83e-6fe5cacd0063" xlink:to="loc_us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable_01a05da9-23c9-710d-83fc-09c16416c4bd" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_01a05da9-23c9-7591-87c3-f9f5876c3a04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable_01a05da9-23c9-710d-83fc-09c16416c4bd" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_01a05da9-23c9-7591-87c3-f9f5876c3a04" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_01a05da9-23c9-7591-87c3-f9f5876c3a04_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_01a05da9-23c9-7591-87c3-f9f5876c3a04" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_01a05da9-23c9-7591-87c3-f9f5876c3a04_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_01a05da9-23c9-77fa-ba15-ae9cdee430b3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_01a05da9-23c9-7591-87c3-f9f5876c3a04" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_01a05da9-23c9-77fa-ba15-ae9cdee430b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_TrustAccountsMember_01a05da9-23c9-7e33-9421-7c44023cc6d8" xlink:href="glre-20260930.xsd#glre_TrustAccountsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_01a05da9-23c9-77fa-ba15-ae9cdee430b3" xlink:to="loc_glre_TrustAccountsMember_01a05da9-23c9-7e33-9421-7c44023cc6d8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CashCollateralLettersofCreditIssuedMember_01a05da9-23c9-7daf-8aa1-70ae41050f7a" xlink:href="glre-20260930.xsd#glre_CashCollateralLettersofCreditIssuedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_01a05da9-23c9-77fa-ba15-ae9cdee430b3" xlink:to="loc_glre_CashCollateralLettersofCreditIssuedMember_01a05da9-23c9-7daf-8aa1-70ae41050f7a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CashSecuringDebtFacilityMember_01a05da9-23c9-7c28-8f52-a6ca23e1f8d2" xlink:href="glre-20260930.xsd#glre_CashSecuringDebtFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_01a05da9-23c9-77fa-ba15-ae9cdee430b3" xlink:to="loc_glre_CashSecuringDebtFacilityMember_01a05da9-23c9-7c28-8f52-a6ca23e1f8d2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OtherCashAndCashEquivalentsMember_01a05da9-23c9-763b-acbe-57236a85d1ca" xlink:href="glre-20260930.xsd#glre_OtherCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_01a05da9-23c9-77fa-ba15-ae9cdee430b3" xlink:to="loc_glre_OtherCashAndCashEquivalentsMember_01a05da9-23c9-763b-acbe-57236a85d1ca" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalents_01a05da9-23c9-7072-a421-e3eebb96414a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_01a05da9-23c9-7b62-a83e-6fe5cacd0063" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalents_01a05da9-23c9-7072-a421-e3eebb96414a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_01a05da9-23c9-75f1-ab8d-793677e5add5" 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_RestrictedCashAndCashEquivalentsItemsLineItems_01a05da9-23c9-7b62-a83e-6fe5cacd0063" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_01a05da9-23c9-75f1-ab8d-793677e5add5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_01a05da9-23c9-7218-adfe-36a584a9c746" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_01a05da9-23c9-7b62-a83e-6fe5cacd0063" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_01a05da9-23c9-7218-adfe-36a584a9c746" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/FAIRVALUEMEASUREMENTSNarrativeDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#FAIRVALUEMEASUREMENTSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/FAIRVALUEMEASUREMENTSNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_01a05da9-23c9-72f1-8fed-53c79f4b9c70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_01a05da9-23c9-713c-bd19-a3eec519fb3d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_01a05da9-23c9-72f1-8fed-53c79f4b9c70" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_01a05da9-23c9-713c-bd19-a3eec519fb3d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a05da9-23c9-70d3-bcd5-182112b708c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_01a05da9-23c9-713c-bd19-a3eec519fb3d" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a05da9-23c9-70d3-bcd5-182112b708c4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23c9-70d3-bcd5-182112b708c4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a05da9-23c9-70d3-bcd5-182112b708c4" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23c9-70d3-bcd5-182112b708c4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23c9-7109-a153-2e226e903db1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a05da9-23c9-70d3-bcd5-182112b708c4" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23c9-7109-a153-2e226e903db1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsNonrecurringMember_01a05da9-23c9-78fe-a2ff-81aca881167f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsNonrecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23c9-7109-a153-2e226e903db1" xlink:to="loc_us-gaap_FairValueMeasurementsNonrecurringMember_01a05da9-23c9-78fe-a2ff-81aca881167f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeAxis_01a05da9-23c9-75c1-9503-5ccb56d7fa43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_01a05da9-23c9-713c-bd19-a3eec519fb3d" xlink:to="loc_us-gaap_InvestmentTypeAxis_01a05da9-23c9-75c1-9503-5ccb56d7fa43" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-75c1-9503-5ccb56d7fa43_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_01a05da9-23c9-75c1-9503-5ccb56d7fa43" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-75c1-9503-5ccb56d7fa43_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7007-a7b5-08e53a9cd773" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentTypeCategorizationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_01a05da9-23c9-75c1-9503-5ccb56d7fa43" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7007-a7b5-08e53a9cd773" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_PrivateInvestmentsAndUnlistedEquitySecuritiesMember_01a05da9-23c9-7481-9f10-ffcae7c6d541" xlink:href="glre-20260930.xsd#glre_PrivateInvestmentsAndUnlistedEquitySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_01a05da9-23c9-7007-a7b5-08e53a9cd773" xlink:to="loc_glre_PrivateInvestmentsAndUnlistedEquitySecuritiesMember_01a05da9-23c9-7481-9f10-ffcae7c6d541" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount_01a05da9-23c9-7517-bdda-fc2c0912827b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_01a05da9-23c9-72f1-8fed-53c79f4b9c70" xlink:to="loc_us-gaap_EquitySecuritiesWithoutReadilyDeterminableFairValueAmount_01a05da9-23c9-7517-bdda-fc2c0912827b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInvestments_01a05da9-23c9-78d8-8b43-130132448c8c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_01a05da9-23c9-72f1-8fed-53c79f4b9c70" xlink:to="loc_us-gaap_OtherInvestments_01a05da9-23c9-78d8-8b43-130132448c8c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/FAIRVALUEMEASUREMENTSScheduleofAssetsMeasuredatFairValueonaNonrecurringBasisDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#FAIRVALUEMEASUREMENTSScheduleofAssetsMeasuredatFairValueonaNonrecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/FAIRVALUEMEASUREMENTSScheduleofAssetsMeasuredatFairValueonaNonrecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_01a05da9-23c9-750c-9ba4-cb0f38eeb834" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_01a05da9-23c9-7e06-ad3b-83319211973a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_01a05da9-23c9-750c-9ba4-cb0f38eeb834" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_01a05da9-23c9-7e06-ad3b-83319211973a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_MeasurementPeriodAxis_01a05da9-23c9-7e16-b516-ce8ccc5aa704" xlink:href="glre-20260930.xsd#glre_MeasurementPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_01a05da9-23c9-7e06-ad3b-83319211973a" xlink:to="loc_glre_MeasurementPeriodAxis_01a05da9-23c9-7e16-b516-ce8ccc5aa704" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_MeasurementPeriodDomain_01a05da9-23c9-7e16-b516-ce8ccc5aa704_default" xlink:href="glre-20260930.xsd#glre_MeasurementPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_glre_MeasurementPeriodAxis_01a05da9-23c9-7e16-b516-ce8ccc5aa704" xlink:to="loc_glre_MeasurementPeriodDomain_01a05da9-23c9-7e16-b516-ce8ccc5aa704_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_MeasurementPeriodDomain_01a05da9-23c9-741f-b228-d6288e052057" xlink:href="glre-20260930.xsd#glre_MeasurementPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_glre_MeasurementPeriodAxis_01a05da9-23c9-7e16-b516-ce8ccc5aa704" xlink:to="loc_glre_MeasurementPeriodDomain_01a05da9-23c9-741f-b228-d6288e052057" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_MeasurementPeriodOneMember_01a05da9-23c9-761f-9655-aa2274a47d4f" xlink:href="glre-20260930.xsd#glre_MeasurementPeriodOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_MeasurementPeriodDomain_01a05da9-23c9-741f-b228-d6288e052057" xlink:to="loc_glre_MeasurementPeriodOneMember_01a05da9-23c9-761f-9655-aa2274a47d4f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_MeasurementPeriodTwoMember_01a05da9-23c9-74c4-bf28-22f25151905a" xlink:href="glre-20260930.xsd#glre_MeasurementPeriodTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_MeasurementPeriodDomain_01a05da9-23c9-741f-b228-d6288e052057" xlink:to="loc_glre_MeasurementPeriodTwoMember_01a05da9-23c9-74c4-bf28-22f25151905a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_MeasurementPeriodThreeMember_01a05da9-23c9-7946-85a6-68780f177a96" xlink:href="glre-20260930.xsd#glre_MeasurementPeriodThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_MeasurementPeriodDomain_01a05da9-23c9-741f-b228-d6288e052057" xlink:to="loc_glre_MeasurementPeriodThreeMember_01a05da9-23c9-7946-85a6-68780f177a96" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_01a05da9-23c9-795d-a275-fb5e00893cd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_01a05da9-23c9-750c-9ba4-cb0f38eeb834" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_01a05da9-23c9-795d-a275-fb5e00893cd8" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/FAIRVALUEMEASUREMENTSScheduleofFairValueAssetsMeasuredatFairValueonaRecurringBasisDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#FAIRVALUEMEASUREMENTSScheduleofFairValueAssetsMeasuredatFairValueonaRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/FAIRVALUEMEASUREMENTSScheduleofFairValueAssetsMeasuredatFairValueonaRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a05da9-23ca-7ab8-a95d-998e513b9246" 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_01a05da9-23c9-715d-85f5-77c761732129" 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_01a05da9-23ca-7ab8-a95d-998e513b9246" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a05da9-23c9-715d-85f5-77c761732129" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_01a05da9-23c9-7e10-ab09-e404875372bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a05da9-23c9-715d-85f5-77c761732129" xlink:to="loc_us-gaap_FinancialInstrumentAxis_01a05da9-23c9-7e10-ab09-e404875372bb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7e10-ab09-e404875372bb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01a05da9-23c9-7e10-ab09-e404875372bb" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7e10-ab09-e404875372bb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7604-ba60-59c064b9dd0c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01a05da9-23c9-7e10-ab09-e404875372bb" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7604-ba60-59c064b9dd0c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_01a05da9-23c9-7e53-be4f-3dfab85930f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USGovernmentAgenciesDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7604-ba60-59c064b9dd0c" xlink:to="loc_us-gaap_USGovernmentAgenciesDebtSecuritiesMember_01a05da9-23c9-7e53-be4f-3dfab85930f5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_01a05da9-23c9-72e0-bab5-0f0852ffafd1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7604-ba60-59c064b9dd0c" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_01a05da9-23c9-72e0-bab5-0f0852ffafd1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateBondSecuritiesMember_01a05da9-23ca-75c8-91de-a1ca4504e1f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateBondSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7604-ba60-59c064b9dd0c" xlink:to="loc_us-gaap_CorporateBondSecuritiesMember_01a05da9-23ca-75c8-91de-a1ca4504e1f7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_01a05da9-23ca-7173-8428-e3bda414a37f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-23c9-7604-ba60-59c064b9dd0c" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_01a05da9-23ca-7173-8428-e3bda414a37f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a05da9-23ca-7701-a368-1780ff3b458e" 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_01a05da9-23c9-715d-85f5-77c761732129" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_01a05da9-23ca-7701-a368-1780ff3b458e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a05da9-23ca-7701-a368-1780ff3b458e_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_01a05da9-23ca-7701-a368-1780ff3b458e" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a05da9-23ca-7701-a368-1780ff3b458e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a05da9-23ca-7f59-9966-7068a936baf2" 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_01a05da9-23ca-7701-a368-1780ff3b458e" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_01a05da9-23ca-7f59-9966-7068a936baf2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_01a05da9-23ca-78c6-9624-ca3631394873" 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_01a05da9-23ca-7f59-9966-7068a936baf2" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_01a05da9-23ca-78c6-9624-ca3631394873" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_01a05da9-23ca-70f8-a8bb-cc02e8cf9a8f" 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_01a05da9-23ca-7f59-9966-7068a936baf2" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_01a05da9-23ca-70f8-a8bb-cc02e8cf9a8f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_01a05da9-23ca-773e-ad7f-4be6d7da93e6" 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_01a05da9-23ca-7f59-9966-7068a936baf2" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_01a05da9-23ca-773e-ad7f-4be6d7da93e6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a05da9-23ca-7057-89fd-91bff7c71239" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_01a05da9-23c9-715d-85f5-77c761732129" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a05da9-23ca-7057-89fd-91bff7c71239" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23ca-7057-89fd-91bff7c71239_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a05da9-23ca-7057-89fd-91bff7c71239" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23ca-7057-89fd-91bff7c71239_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23ca-75f2-b5e7-0e6c32d3484d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_01a05da9-23ca-7057-89fd-91bff7c71239" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23ca-75f2-b5e7-0e6c32d3484d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_01a05da9-23ca-7037-b0f1-212f6cd9128c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_01a05da9-23ca-75f2-b5e7-0e6c32d3484d" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_01a05da9-23ca-7037-b0f1-212f6cd9128c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecuritiesDebt_01a05da9-23ca-7f45-a108-5243ea16c59a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_01a05da9-23ca-7ab8-a95d-998e513b9246" xlink:to="loc_us-gaap_TradingSecuritiesDebt_01a05da9-23ca-7f45-a108-5243ea16c59a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/LOSSANDLOSSADJUSTMENTEXPENSERESERVESNarrativeDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#LOSSANDLOSSADJUSTMENTEXPENSERESERVESNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/LOSSANDLOSSADJUSTMENTEXPENSERESERVESNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:to="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a05da9-23ca-7883-8b35-24241ddec62e" 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_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:to="loc_srt_ConsolidationItemsAxis_01a05da9-23ca-7883-8b35-24241ddec62e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7883-8b35-24241ddec62e_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_01a05da9-23ca-7883-8b35-24241ddec62e" xlink:to="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7883-8b35-24241ddec62e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7ec8-84c7-55155cbb3f50" 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_01a05da9-23ca-7883-8b35-24241ddec62e" xlink:to="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7ec8-84c7-55155cbb3f50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a05da9-23ca-7de9-89bb-e38442ef076d" 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_01a05da9-23ca-7ec8-84c7-55155cbb3f50" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a05da9-23ca-7de9-89bb-e38442ef076d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceContractAxis_01a05da9-23ca-7b2f-876b-42ffa039f8e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReinsuranceContractAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:to="loc_us-gaap_ReinsuranceContractAxis_01a05da9-23ca-7b2f-876b-42ffa039f8e6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a05da9-23ca-7bda-bc6b-0c9570184f79" 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_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a05da9-23ca-7bda-bc6b-0c9570184f79" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a05da9-23ca-7bda-bc6b-0c9570184f79_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_01a05da9-23ca-7bda-bc6b-0c9570184f79" xlink:to="loc_us-gaap_SegmentDomain_01a05da9-23ca-7bda-bc6b-0c9570184f79_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a05da9-23ca-7da4-bfbd-781d94cd62c0" 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_01a05da9-23ca-7bda-bc6b-0c9570184f79" xlink:to="loc_us-gaap_SegmentDomain_01a05da9-23ca-7da4-bfbd-781d94cd62c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OpenMarketMember_01a05da9-23ca-7529-8dc5-1a4c91225b8b" xlink:href="glre-20260930.xsd#glre_OpenMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a05da9-23ca-7da4-bfbd-781d94cd62c0" xlink:to="loc_glre_OpenMarketMember_01a05da9-23ca-7529-8dc5-1a4c91225b8b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_InnovationsMember_01a05da9-23ca-79f0-9a2c-d8555702f173" xlink:href="glre-20260930.xsd#glre_InnovationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a05da9-23ca-7da4-bfbd-781d94cd62c0" xlink:to="loc_glre_InnovationsMember_01a05da9-23ca-79f0-9a2c-d8555702f173" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossFromCatastrophes_01a05da9-23ca-7ffd-90c4-7ccbe1f8711d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossFromCatastrophes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:to="loc_us-gaap_LossFromCatastrophes_01a05da9-23ca-7ffd-90c4-7ccbe1f8711d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_01a05da9-23ca-71c6-baa8-6d3e1f127859" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:to="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_01a05da9-23ca-71c6-baa8-6d3e1f127859" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InsuranceRecoveries_01a16b60-9b60-778c-81f8-f45507cb9109" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InsuranceRecoveries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:to="loc_us-gaap_InsuranceRecoveries_01a16b60-9b60-778c-81f8-f45507cb9109" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/LOSSANDLOSSADJUSTMENTEXPENSERESERVESNarrativeDetails_1" xlink:type="simple" xlink:href="glre-20260930.xsd#LOSSANDLOSSADJUSTMENTEXPENSERESERVESNarrativeDetails_1"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/LOSSANDLOSSADJUSTMENTEXPENSERESERVESNarrativeDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:to="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a05da9-23ca-7883-8b35-24241ddec62e" 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_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:to="loc_srt_ConsolidationItemsAxis_01a05da9-23ca-7883-8b35-24241ddec62e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7883-8b35-24241ddec62e_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_01a05da9-23ca-7883-8b35-24241ddec62e" xlink:to="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7883-8b35-24241ddec62e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7ec8-84c7-55155cbb3f50" 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_01a05da9-23ca-7883-8b35-24241ddec62e" xlink:to="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7ec8-84c7-55155cbb3f50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a05da9-23ca-7de9-89bb-e38442ef076d" 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_01a05da9-23ca-7ec8-84c7-55155cbb3f50" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a05da9-23ca-7de9-89bb-e38442ef076d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a05da9-23ca-7bda-bc6b-0c9570184f79" 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_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-7093-ac0d-4f291a76e856" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a05da9-23ca-7bda-bc6b-0c9570184f79" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a05da9-23ca-7bda-bc6b-0c9570184f79_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_01a05da9-23ca-7bda-bc6b-0c9570184f79" xlink:to="loc_us-gaap_SegmentDomain_01a05da9-23ca-7bda-bc6b-0c9570184f79_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a05da9-23ca-7da4-bfbd-781d94cd62c0" 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_01a05da9-23ca-7bda-bc6b-0c9570184f79" xlink:to="loc_us-gaap_SegmentDomain_01a05da9-23ca-7da4-bfbd-781d94cd62c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OpenMarketMember_01a05da9-23ca-7529-8dc5-1a4c91225b8b" xlink:href="glre-20260930.xsd#glre_OpenMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a05da9-23ca-7da4-bfbd-781d94cd62c0" xlink:to="loc_glre_OpenMarketMember_01a05da9-23ca-7529-8dc5-1a4c91225b8b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_InnovationsMember_01a05da9-23ca-79f0-9a2c-d8555702f173" xlink:href="glre-20260930.xsd#glre_InnovationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a05da9-23ca-7da4-bfbd-781d94cd62c0" xlink:to="loc_glre_InnovationsMember_01a05da9-23ca-79f0-9a2c-d8555702f173" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossFromCatastrophes_01a05da9-23ca-7ffd-90c4-7ccbe1f8711d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossFromCatastrophes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:to="loc_us-gaap_LossFromCatastrophes_01a05da9-23ca-7ffd-90c4-7ccbe1f8711d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_01a05da9-23ca-71c6-baa8-6d3e1f127859" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:to="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_01a05da9-23ca-71c6-baa8-6d3e1f127859" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InsuranceRecoveries_01a16b60-9b60-778c-81f8-f45507cb9109" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InsuranceRecoveries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-74a5-a304-5d421ce24396" xlink:to="loc_us-gaap_InsuranceRecoveries_01a16b60-9b60-778c-81f8-f45507cb9109" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/LOSSANDLOSSADJUSTMENTEXPENSERESERVESScheduleofNetPriorYearReserveDevelopmentbySegmentDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#LOSSANDLOSSADJUSTMENTEXPENSERESERVESScheduleofNetPriorYearReserveDevelopmentbySegmentDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/LOSSANDLOSSADJUSTMENTEXPENSERESERVESScheduleofNetPriorYearReserveDevelopmentbySegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-7b1e-8a31-a65ad5f2f77d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-722c-90a4-6f3c48fdb619" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-7b1e-8a31-a65ad5f2f77d" xlink:to="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-722c-90a4-6f3c48fdb619" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a05da9-23ca-7cef-9961-afe0640b8c1f" 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_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-722c-90a4-6f3c48fdb619" xlink:to="loc_srt_ConsolidationItemsAxis_01a05da9-23ca-7cef-9961-afe0640b8c1f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7cef-9961-afe0640b8c1f_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_01a05da9-23ca-7cef-9961-afe0640b8c1f" xlink:to="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-7cef-9961-afe0640b8c1f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-71a1-b6a2-23ff4684a1e4" 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_01a05da9-23ca-7cef-9961-afe0640b8c1f" xlink:to="loc_srt_ConsolidationItemsDomain_01a05da9-23ca-71a1-b6a2-23ff4684a1e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a05da9-23ca-7567-b261-5a7929069b31" 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_01a05da9-23ca-71a1-b6a2-23ff4684a1e4" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a05da9-23ca-7567-b261-5a7929069b31" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_01a05da9-23ca-7821-9602-50a74bbf63b6" 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_01a05da9-23ca-71a1-b6a2-23ff4684a1e4" xlink:to="loc_us-gaap_CorporateNonSegmentMember_01a05da9-23ca-7821-9602-50a74bbf63b6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a05da9-23ca-7deb-b93d-a1a4793ae724" 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_LiabilityForClaimsAndClaimsAdjustmentExpenseTable_01a05da9-23ca-722c-90a4-6f3c48fdb619" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a05da9-23ca-7deb-b93d-a1a4793ae724" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a05da9-23ca-7deb-b93d-a1a4793ae724_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_01a05da9-23ca-7deb-b93d-a1a4793ae724" xlink:to="loc_us-gaap_SegmentDomain_01a05da9-23ca-7deb-b93d-a1a4793ae724_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a05da9-23ca-7bf6-9e0f-5413aa70dd92" 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_01a05da9-23ca-7deb-b93d-a1a4793ae724" xlink:to="loc_us-gaap_SegmentDomain_01a05da9-23ca-7bf6-9e0f-5413aa70dd92" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OpenMarketMember_01a05da9-23ca-7d64-8022-be2955845d95" xlink:href="glre-20260930.xsd#glre_OpenMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a05da9-23ca-7bf6-9e0f-5413aa70dd92" xlink:to="loc_glre_OpenMarketMember_01a05da9-23ca-7d64-8022-be2955845d95" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_InnovationsMember_01a05da9-23ca-78eb-86eb-01ec9b7ce859" xlink:href="glre-20260930.xsd#glre_InnovationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a05da9-23ca-7bf6-9e0f-5413aa70dd92" xlink:to="loc_glre_InnovationsMember_01a05da9-23ca-78eb-86eb-01ec9b7ce859" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_01a05da9-23ca-7c7d-aeb9-c8e765591b14" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilityForClaimsAndClaimsAdjustmentExpenseLineItems_01a05da9-23ca-7b1e-8a31-a65ad5f2f77d" xlink:to="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_01a05da9-23ca-7c7d-aeb9-c8e765591b14" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/RETROCESSIONScheduleofBreakdownofLossesRecoverableonaGrossandNetofCollateralBasisDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#RETROCESSIONScheduleofBreakdownofLossesRecoverableonaGrossandNetofCollateralBasisDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/RETROCESSIONScheduleofBreakdownofLossesRecoverableonaGrossandNetofCollateralBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7401-ad3b-d9270c534be1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CededCreditRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-7f60-b9a7-82a5f217efbc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CededCreditRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7401-ad3b-d9270c534be1" xlink:to="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-7f60-b9a7-82a5f217efbc" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestAxis_01a05da9-2468-75c2-8bc1-88ae1f5aa811" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CreditRatingAMBestAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-7f60-b9a7-82a5f217efbc" xlink:to="loc_srt_CreditRatingAMBestAxis_01a05da9-2468-75c2-8bc1-88ae1f5aa811" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestDomain_01a05da9-2468-75c2-8bc1-88ae1f5aa811_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CreditRatingAMBestDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CreditRatingAMBestAxis_01a05da9-2468-75c2-8bc1-88ae1f5aa811" xlink:to="loc_srt_CreditRatingAMBestDomain_01a05da9-2468-75c2-8bc1-88ae1f5aa811_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingAMBestDomain_01a05da9-2468-7bef-90c3-dd7a0aa6bc61" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CreditRatingAMBestDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CreditRatingAMBestAxis_01a05da9-2468-75c2-8bc1-88ae1f5aa811" xlink:to="loc_srt_CreditRatingAMBestDomain_01a05da9-2468-7bef-90c3-dd7a0aa6bc61" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_AOrBetterByA.M.BestMember_01a05da9-2468-73ea-bb6c-7acef1914749" xlink:href="glre-20260930.xsd#glre_AOrBetterByA.M.BestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CreditRatingAMBestDomain_01a05da9-2468-7bef-90c3-dd7a0aa6bc61" xlink:to="loc_glre_AOrBetterByA.M.BestMember_01a05da9-2468-73ea-bb6c-7acef1914749" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_NotRatedMember_01a05da9-2468-7fac-8aaa-016ed82bd4d3" xlink:href="glre-20260930.xsd#glre_NotRatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CreditRatingAMBestDomain_01a05da9-2468-7bef-90c3-dd7a0aa6bc61" xlink:to="loc_glre_NotRatedMember_01a05da9-2468-7fac-8aaa-016ed82bd4d3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_01a05da9-2468-79db-8922-e44013a31a07" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-7f60-b9a7-82a5f217efbc" xlink:to="loc_us-gaap_FinancialInstrumentAxis_01a05da9-2468-79db-8922-e44013a31a07" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-2468-79db-8922-e44013a31a07_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01a05da9-2468-79db-8922-e44013a31a07" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-2468-79db-8922-e44013a31a07_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-2468-79b0-ad30-b6086afeba49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_01a05da9-2468-79db-8922-e44013a31a07" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-2468-79b0-ad30-b6086afeba49" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_RetrocessionPortfolioMember_01a05da9-2468-73b1-8297-a28575cf6663" xlink:href="glre-20260930.xsd#glre_RetrocessionPortfolioMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_01a05da9-2468-79b0-ad30-b6086afeba49" xlink:to="loc_glre_RetrocessionPortfolioMember_01a05da9-2468-73b1-8297-a28575cf6663" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceRecoverablesGross_01a05da9-2468-75a7-8d63-3a29fff22c9f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReinsuranceRecoverablesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7401-ad3b-d9270c534be1" xlink:to="loc_us-gaap_ReinsuranceRecoverablesGross_01a05da9-2468-75a7-8d63-3a29fff22c9f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceRecoverablesAllowance_01a05da9-2468-73c8-b061-f63d4d448150" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReinsuranceRecoverablesAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7401-ad3b-d9270c534be1" xlink:to="loc_us-gaap_ReinsuranceRecoverablesAllowance_01a05da9-2468-73c8-b061-f63d4d448150" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReinsuranceRecoverables_01a05da9-2468-73e9-9d2f-915651d96934" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReinsuranceRecoverables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7401-ad3b-d9270c534be1" xlink:to="loc_us-gaap_ReinsuranceRecoverables_01a05da9-2468-73e9-9d2f-915651d96934" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ReinsuranceRecoverablesNetOfCollateral_01a05da9-2468-7e39-abde-abb688f6d5cc" xlink:href="glre-20260930.xsd#glre_ReinsuranceRecoverablesNetOfCollateral"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7401-ad3b-d9270c534be1" xlink:to="loc_glre_ReinsuranceRecoverablesNetOfCollateral_01a05da9-2468-7e39-abde-abb688f6d5cc" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/RETROCESSIONNarrativeDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#RETROCESSIONNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/RETROCESSIONNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7020-83f2-3ceec33b3c03" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CededCreditRiskLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-756d-be02-47c458df88ea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CededCreditRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7020-83f2-3ceec33b3c03" xlink:to="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-756d-be02-47c458df88ea" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ResinsurersAxis_01a05da9-2468-7d78-97fd-cb10f26011ec" xlink:href="glre-20260930.xsd#glre_ResinsurersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-756d-be02-47c458df88ea" xlink:to="loc_glre_ResinsurersAxis_01a05da9-2468-7d78-97fd-cb10f26011ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ResinsurersDomain_01a05da9-2468-7d78-97fd-cb10f26011ec_default" xlink:href="glre-20260930.xsd#glre_ResinsurersDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_glre_ResinsurersAxis_01a05da9-2468-7d78-97fd-cb10f26011ec" xlink:to="loc_glre_ResinsurersDomain_01a05da9-2468-7d78-97fd-cb10f26011ec_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ResinsurersDomain_01a05da9-2468-7dc5-afb8-6dd12cd0a7b8" xlink:href="glre-20260930.xsd#glre_ResinsurersDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_glre_ResinsurersAxis_01a05da9-2468-7d78-97fd-cb10f26011ec" xlink:to="loc_glre_ResinsurersDomain_01a05da9-2468-7dc5-afb8-6dd12cd0a7b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_FourReinsurersMember_01a05da9-2468-763a-802d-553c5d768d9f" xlink:href="glre-20260930.xsd#glre_FourReinsurersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_ResinsurersDomain_01a05da9-2468-7dc5-afb8-6dd12cd0a7b8" xlink:to="loc_glre_FourReinsurersMember_01a05da9-2468-763a-802d-553c5d768d9f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ThreeReinsurersMember_01a05da9-2468-7352-a57c-54dd4218fec9" xlink:href="glre-20260930.xsd#glre_ThreeReinsurersMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_ResinsurersDomain_01a05da9-2468-7dc5-afb8-6dd12cd0a7b8" xlink:to="loc_glre_ThreeReinsurersMember_01a05da9-2468-7352-a57c-54dd4218fec9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_01a05da9-2468-71fd-ba43-2de807bee48d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-756d-be02-47c458df88ea" xlink:to="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_01a05da9-2468-71fd-ba43-2de807bee48d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a05da9-2468-71fd-ba43-2de807bee48d_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_01a05da9-2468-71fd-ba43-2de807bee48d" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a05da9-2468-71fd-ba43-2de807bee48d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a05da9-2468-7ae5-9097-09e514314ef9" 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_01a05da9-2468-71fd-ba43-2de807bee48d" xlink:to="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a05da9-2468-7ae5-9097-09e514314ef9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_TotalLossAndLossAdjustmentExpenseRecoverabilityMember_01a05da9-2468-76cf-a8b8-e1d79239c27e" xlink:href="glre-20260930.xsd#glre_TotalLossAndLossAdjustmentExpenseRecoverabilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_01a05da9-2468-7ae5-9097-09e514314ef9" xlink:to="loc_glre_TotalLossAndLossAdjustmentExpenseRecoverabilityMember_01a05da9-2468-76cf-a8b8-e1d79239c27e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_01a05da9-2468-775d-b8b3-00a63095fa7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CededCreditRiskTable_01a05da9-2468-756d-be02-47c458df88ea" xlink:to="loc_us-gaap_ConcentrationRiskByTypeAxis_01a05da9-2468-775d-b8b3-00a63095fa7c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_01a05da9-2468-775d-b8b3-00a63095fa7c_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_01a05da9-2468-775d-b8b3-00a63095fa7c" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_01a05da9-2468-775d-b8b3-00a63095fa7c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_01a05da9-2468-7be3-b96d-9fcc9f6087b6" 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_01a05da9-2468-775d-b8b3-00a63095fa7c" xlink:to="loc_us-gaap_ConcentrationRiskTypeDomain_01a05da9-2468-7be3-b96d-9fcc9f6087b6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ReinsuranceConcentrationRiskMember_01a05da9-2468-705f-a93d-c6bc80c148f9" xlink:href="glre-20260930.xsd#glre_ReinsuranceConcentrationRiskMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_01a05da9-2468-7be3-b96d-9fcc9f6087b6" xlink:to="loc_glre_ReinsuranceConcentrationRiskMember_01a05da9-2468-705f-a93d-c6bc80c148f9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure_01a05da9-2468-7c73-b896-6bf31cba1432" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CededCreditRiskLineItems_01a05da9-2468-7020-83f2-3ceec33b3c03" xlink:to="loc_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure_01a05da9-2468-7c73-b896-6bf31cba1432" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/DEBTANDCREDITFACILITIESScheduleofLetterofCreditLOCFacilitiesDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#DEBTANDCREDITFACILITIESScheduleofLetterofCreditLOCFacilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/DEBTANDCREDITFACILITIESScheduleofLetterofCreditLOCFacilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_01a05da9-2468-7b85-99a6-d042fa83811d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-75de-8ec3-31da9b70d589" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_01a05da9-2468-7b85-99a6-d042fa83811d" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-75de-8ec3-31da9b70d589" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_01a05da9-2468-71c3-ba69-4aa0f8891539" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-75de-8ec3-31da9b70d589" xlink:to="loc_us-gaap_CreditFacilityAxis_01a05da9-2468-71c3-ba69-4aa0f8891539" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-71c3-ba69-4aa0f8891539_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_01a05da9-2468-71c3-ba69-4aa0f8891539" xlink:to="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-71c3-ba69-4aa0f8891539_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-74b9-8070-d1c366a07a16" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_01a05da9-2468-71c3-ba69-4aa0f8891539" xlink:to="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-74b9-8070-d1c366a07a16" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialStandbyLetterOfCreditMember_01a05da9-2468-7272-9478-b188231687a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialStandbyLetterOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-74b9-8070-d1c366a07a16" xlink:to="loc_us-gaap_FinancialStandbyLetterOfCreditMember_01a05da9-2468-7272-9478-b188231687a5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityAxis_01a05da9-2468-72d4-85c7-3785881c3e4d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-75de-8ec3-31da9b70d589" xlink:to="loc_us-gaap_LineOfCreditFacilityAxis_01a05da9-2468-72d4-85c7-3785881c3e4d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-72d4-85c7-3785881c3e4d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_01a05da9-2468-72d4-85c7-3785881c3e4d" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-72d4-85c7-3785881c3e4d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7f43-be61-ca3709a14b11" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_01a05da9-2468-72d4-85c7-3785881c3e4d" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7f43-be61-ca3709a14b11" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exch_HSBC_01a05da9-2468-7187-8561-9aaa38cb7509" xlink:href="https://xbrl.sec.gov/exch/2026/exch-2026.xsd#exch_HSBC"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7f43-be61-ca3709a14b11" xlink:to="loc_exch_HSBC_01a05da9-2468-7187-8561-9aaa38cb7509" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CitibankMember_01a05da9-2468-71ac-bb5d-54d17593e79e" xlink:href="glre-20260930.xsd#glre_CitibankMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7f43-be61-ca3709a14b11" xlink:to="loc_glre_CitibankMember_01a05da9-2468-71ac-bb5d-54d17593e79e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CIBCMember_01a05da9-2468-7ff6-842d-7e74ff0089fa" xlink:href="glre-20260930.xsd#glre_CIBCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7f43-be61-ca3709a14b11" xlink:to="loc_glre_CIBCMember_01a05da9-2468-7ff6-842d-7e74ff0089fa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CitibankFALMember_01a05da9-2468-7132-ae9f-2c14a3065191" xlink:href="glre-20260930.xsd#glre_CitibankFALMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7f43-be61-ca3709a14b11" xlink:to="loc_glre_CitibankFALMember_01a05da9-2468-7132-ae9f-2c14a3065191" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a05da9-2468-75ed-a2f0-2d056d4d74a0" 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_LineOfCreditFacilityLineItems_01a05da9-2468-7b85-99a6-d042fa83811d" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a05da9-2468-75ed-a2f0-2d056d4d74a0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_LineOfCreditFacilityAmountsDrawn_01a05da9-2468-7604-a327-956cc5aa8270" xlink:href="glre-20260930.xsd#glre_LineOfCreditFacilityAmountsDrawn"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_01a05da9-2468-7b85-99a6-d042fa83811d" xlink:to="loc_glre_LineOfCreditFacilityAmountsDrawn_01a05da9-2468-7604-a327-956cc5aa8270" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/DEBTANDCREDITFACILITIESNarrativeDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#DEBTANDCREDITFACILITIESNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/DEBTANDCREDITFACILITIESNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_01a05da9-2468-708f-a338-0e47e3b0cb21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-730f-acd2-b7647fb5b57c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_01a05da9-2468-708f-a338-0e47e3b0cb21" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-730f-acd2-b7647fb5b57c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_01a05da9-2468-7815-8e67-d17011ade07f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-730f-acd2-b7647fb5b57c" xlink:to="loc_us-gaap_CreditFacilityAxis_01a05da9-2468-7815-8e67-d17011ade07f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-7815-8e67-d17011ade07f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_01a05da9-2468-7815-8e67-d17011ade07f" xlink:to="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-7815-8e67-d17011ade07f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-7eba-ace7-955797851c1b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_01a05da9-2468-7815-8e67-d17011ade07f" xlink:to="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-7eba-ace7-955797851c1b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialStandbyLetterOfCreditMember_01a05da9-2468-79dd-8511-14be30bb3c67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialStandbyLetterOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01a05da9-2468-7eba-ace7-955797851c1b" xlink:to="loc_us-gaap_FinancialStandbyLetterOfCreditMember_01a05da9-2468-79dd-8511-14be30bb3c67" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityAxis_01a05da9-2468-791a-9e95-f11fed205b39" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-730f-acd2-b7647fb5b57c" xlink:to="loc_us-gaap_LineOfCreditFacilityAxis_01a05da9-2468-791a-9e95-f11fed205b39" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-791a-9e95-f11fed205b39_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_01a05da9-2468-791a-9e95-f11fed205b39" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-791a-9e95-f11fed205b39_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7362-afad-4da543173a17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLenderDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_01a05da9-2468-791a-9e95-f11fed205b39" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7362-afad-4da543173a17" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CIBCMember_01a05da9-2468-721a-8693-5864b9f97e55" xlink:href="glre-20260930.xsd#glre_CIBCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7362-afad-4da543173a17" xlink:to="loc_glre_CIBCMember_01a05da9-2468-721a-8693-5864b9f97e55" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CitibankFALMember_01a05da9-2468-7eb1-8d70-d1ee2748e8de" xlink:href="glre-20260930.xsd#glre_CitibankFALMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_01a05da9-2468-7362-afad-4da543173a17" xlink:to="loc_glre_CitibankFALMember_01a05da9-2468-7eb1-8d70-d1ee2748e8de" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a05da9-2468-7a20-aad8-5c5c4e296db1" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_01a05da9-2468-730f-acd2-b7647fb5b57c" xlink:to="loc_dei_LegalEntityAxis_01a05da9-2468-7a20-aad8-5c5c4e296db1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a05da9-2468-7a20-aad8-5c5c4e296db1_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a05da9-2468-7a20-aad8-5c5c4e296db1" xlink:to="loc_dei_EntityDomain_01a05da9-2468-7a20-aad8-5c5c4e296db1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a05da9-2468-73e7-b6d4-18bb84a84dd5" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a05da9-2468-7a20-aad8-5c5c4e296db1" xlink:to="loc_dei_EntityDomain_01a05da9-2468-73e7-b6d4-18bb84a84dd5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_GreenlightReMember_01a05da9-2468-792b-be4e-3372ace7f350" xlink:href="glre-20260930.xsd#glre_GreenlightReMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a05da9-2468-73e7-b6d4-18bb84a84dd5" xlink:to="loc_glre_GreenlightReMember_01a05da9-2468-792b-be4e-3372ace7f350" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_GRILMember_01a05da9-2468-7809-9f7b-be285c2a6bc0" xlink:href="glre-20260930.xsd#glre_GRILMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a05da9-2468-73e7-b6d4-18bb84a84dd5" xlink:to="loc_glre_GRILMember_01a05da9-2468-7809-9f7b-be285c2a6bc0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a05da9-2468-73aa-8b95-97ceac27737a" 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_LineOfCreditFacilityLineItems_01a05da9-2468-708f-a338-0e47e3b0cb21" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_01a05da9-2468-73aa-8b95-97ceac27737a" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/SHARECAPITALNarrativeDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#SHARECAPITALNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/SHARECAPITALNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" 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_01a05da9-2468-7346-bba5-888fffec1d99" 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_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_01a05da9-2468-7346-bba5-888fffec1d99" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-7318-a3be-09b41eb79831" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_01a05da9-2468-7346-bba5-888fffec1d99" xlink:to="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-7318-a3be-09b41eb79831" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-7318-a3be-09b41eb79831_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-7318-a3be-09b41eb79831" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-7318-a3be-09b41eb79831_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-704f-ba79-1c383cc3928b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-7318-a3be-09b41eb79831" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-704f-ba79-1c383cc3928b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_A2025ShareRepurchaseProgramMember_01a05da9-2468-7ed7-9314-6d3116aa651e" xlink:href="glre-20260930.xsd#glre_A2025ShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-704f-ba79-1c383cc3928b" xlink:to="loc_glre_A2025ShareRepurchaseProgramMember_01a05da9-2468-7ed7-9314-6d3116aa651e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_A2026ShareRepurchaseProgramMember_01a05da9-2468-7467-a88e-3a4ee6cf2d55" xlink:href="glre-20260930.xsd#glre_A2026ShareRepurchaseProgramMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-704f-ba79-1c383cc3928b" xlink:to="loc_glre_A2026ShareRepurchaseProgramMember_01a05da9-2468-7467-a88e-3a4ee6cf2d55" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_01a05da9-2468-72c1-bbdc-7cefe6bc1193" 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_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_01a05da9-2468-72c1-bbdc-7cefe6bc1193" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_01a05da9-2468-7239-9c0a-8ca60aab8df4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_01a05da9-2468-7239-9c0a-8ca60aab8df4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_01a05da9-2468-7dcd-b625-36176a6ed011" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_01a05da9-2468-7dcd-b625-36176a6ed011" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_01a05da9-2468-7487-beb7-b5f31fae9f70" 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_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_01a05da9-2468-7487-beb7-b5f31fae9f70" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_01a05da9-2468-7857-a86f-d4eb2ad2a5fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_01a05da9-2468-7857-a86f-d4eb2ad2a5fe" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_01a05da9-2468-7d31-97b7-61694e1bdcaa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_01a05da9-2468-7d31-97b7-61694e1bdcaa" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_01a05da9-2468-7408-b074-1fa982b3b1e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_01a05da9-2468-7bf1-8d3d-ee2b22792ec0" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_01a05da9-2468-7408-b074-1fa982b3b1e7" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/SHARECAPITALScheduleofStockbyClassDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#SHARECAPITALScheduleofStockbyClassDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/SHARECAPITALScheduleofStockbyClassDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_01a188a7-bb2f-72b4-8649-f8d1fb715199" 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_01a188a7-bb2f-776f-b23b-dbbefaa9c461" 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_01a188a7-bb2f-72b4-8649-f8d1fb715199" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_01a188a7-bb2f-776f-b23b-dbbefaa9c461" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualAxis_01a188a7-bb2f-759a-8c55-eaba736f3ce3" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_01a188a7-bb2f-776f-b23b-dbbefaa9c461" xlink:to="loc_srt_TitleOfIndividualAxis_01a188a7-bb2f-759a-8c55-eaba736f3ce3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_01a188a7-bb2f-759a-8c55-eaba736f3ce3_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_TitleOfIndividualAxis_01a188a7-bb2f-759a-8c55-eaba736f3ce3" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_01a188a7-bb2f-759a-8c55-eaba736f3ce3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_01a188a7-bb2f-7cfa-9800-954b6bd7fd31" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_TitleOfIndividualAxis_01a188a7-bb2f-759a-8c55-eaba736f3ce3" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_01a188a7-bb2f-7cfa-9800-954b6bd7fd31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_DirectorMember_01a188a7-ee01-77ee-96a3-8e6979d1dfed" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_DirectorMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_01a188a7-bb2f-7cfa-9800-954b6bd7fd31" xlink:to="loc_srt_DirectorMember_01a188a7-ee01-77ee-96a3-8e6979d1dfed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_01a188a7-bb2f-7aa2-b4ce-4b5ec922bcb8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_01a188a7-bb2f-72b4-8649-f8d1fb715199" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_01a188a7-bb2f-7aa2-b4ce-4b5ec922bcb8" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/SHAREBASEDCOMPENSATIONNarrativeDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#SHAREBASEDCOMPENSATIONNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/SHAREBASEDCOMPENSATIONNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-77fd-99ca-883bac8f4219" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7175-9570-2cb995721d30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-77fd-99ca-883bac8f4219" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7175-9570-2cb995721d30" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_01a05da9-2468-77b6-b020-c1231425adc6" 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_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7175-9570-2cb995721d30" xlink:to="loc_us-gaap_AwardTypeAxis_01a05da9-2468-77b6-b020-c1231425adc6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-77b6-b020-c1231425adc6_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_01a05da9-2468-77b6-b020-c1231425adc6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-77b6-b020-c1231425adc6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-700e-9744-6c1df92af10e" 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_01a05da9-2468-77b6-b020-c1231425adc6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-700e-9744-6c1df92af10e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_PerformanceAndServiceRestrictedStockMember_01a05da9-2468-7a9d-9dd5-98aa641d1bac" xlink:href="glre-20260930.xsd#glre_PerformanceAndServiceRestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-700e-9744-6c1df92af10e" xlink:to="loc_glre_PerformanceAndServiceRestrictedStockMember_01a05da9-2468-7a9d-9dd5-98aa641d1bac" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ServiceRSUsMember_01a05da9-2468-7780-8c3f-94a29d945d85" xlink:href="glre-20260930.xsd#glre_ServiceRSUsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-700e-9744-6c1df92af10e" xlink:to="loc_glre_ServiceRSUsMember_01a05da9-2468-7780-8c3f-94a29d945d85" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_01a05da9-2468-7203-af8b-d4978fa26b0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-700e-9744-6c1df92af10e" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_01a05da9-2468-7203-af8b-d4978fa26b0a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_PerformanceRestrictedStockUnitsMember_01a05da9-2468-736b-a01f-201f18339f00" xlink:href="glre-20260930.xsd#glre_PerformanceRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-700e-9744-6c1df92af10e" xlink:to="loc_glre_PerformanceRestrictedStockUnitsMember_01a05da9-2468-736b-a01f-201f18339f00" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_PerformanceAndServiceRestrictedStockUnitsMember_01a05da9-2468-7fc3-a1ec-89c0b1aa7374" xlink:href="glre-20260930.xsd#glre_PerformanceAndServiceRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-700e-9744-6c1df92af10e" xlink:to="loc_glre_PerformanceAndServiceRestrictedStockUnitsMember_01a05da9-2468-7fc3-a1ec-89c0b1aa7374" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ServiceRestrictedStockMember_01a168d9-7776-7367-ba18-cd365967adb1" xlink:href="glre-20260930.xsd#glre_ServiceRestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-700e-9744-6c1df92af10e" xlink:to="loc_glre_ServiceRestrictedStockMember_01a168d9-7776-7367-ba18-cd365967adb1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_01a05da9-2468-7752-a4f8-fbb03ccac8c2" 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_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7175-9570-2cb995721d30" xlink:to="loc_srt_RangeAxis_01a05da9-2468-7752-a4f8-fbb03ccac8c2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a05da9-2468-7752-a4f8-fbb03ccac8c2_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_01a05da9-2468-7752-a4f8-fbb03ccac8c2" xlink:to="loc_srt_RangeMember_01a05da9-2468-7752-a4f8-fbb03ccac8c2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_01a05da9-2468-7a12-a589-4d866d466a12" 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_01a05da9-2468-7752-a4f8-fbb03ccac8c2" xlink:to="loc_srt_RangeMember_01a05da9-2468-7a12-a589-4d866d466a12" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_01a05da9-2468-7a83-928f-0dbc31401a13" 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_01a05da9-2468-7a12-a589-4d866d466a12" xlink:to="loc_srt_MinimumMember_01a05da9-2468-7a83-928f-0dbc31401a13" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_01a05da9-2468-77e5-bfc1-def7c90a9145" 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_01a05da9-2468-7a12-a589-4d866d466a12" xlink:to="loc_srt_MaximumMember_01a05da9-2468-77e5-bfc1-def7c90a9145" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_01a05da9-2468-7228-961c-9c8e78b748e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-77fd-99ca-883bac8f4219" xlink:to="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_01a05da9-2468-7228-961c-9c8e78b748e1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_01a168d9-7776-7c8b-880f-443fa161b3e4" 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-77fd-99ca-883bac8f4219" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_01a168d9-7776-7c8b-880f-443fa161b3e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_01a05da9-2468-7c16-8f41-219265043318" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-77fd-99ca-883bac8f4219" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_01a05da9-2468-7c16-8f41-219265043318" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_01a05da9-2468-7ee0-8c70-a20cf1d9e270" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-77fd-99ca-883bac8f4219" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_01a05da9-2468-7ee0-8c70-a20cf1d9e270" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_01a05da9-2468-71f0-ab9a-81143a94ae95" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-77fd-99ca-883bac8f4219" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_01a05da9-2468-71f0-ab9a-81143a94ae95" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_01a05da9-2468-726f-a220-123c809dc042" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-77fd-99ca-883bac8f4219" xlink:to="loc_us-gaap_ShareBasedCompensation_01a05da9-2468-726f-a220-123c809dc042" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/SHAREBASEDCOMPENSATIONScheduleofRestrictedStockDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#SHAREBASEDCOMPENSATIONScheduleofRestrictedStockDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/SHAREBASEDCOMPENSATIONScheduleofRestrictedStockDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-7da0-9c02-cfd1a785e567" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7d02-b621-6bda6d1be011" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-7da0-9c02-cfd1a785e567" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7d02-b621-6bda6d1be011" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_01a05da9-2468-7f4c-98a2-7baca4608244" 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_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7d02-b621-6bda6d1be011" xlink:to="loc_us-gaap_AwardTypeAxis_01a05da9-2468-7f4c-98a2-7baca4608244" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7f4c-98a2-7baca4608244_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_01a05da9-2468-7f4c-98a2-7baca4608244" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7f4c-98a2-7baca4608244_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7fbe-9b36-cabfc0e8fb28" 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_01a05da9-2468-7f4c-98a2-7baca4608244" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7fbe-9b36-cabfc0e8fb28" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_PerformanceRestrictedStockMember_01a05da9-2468-7d1c-bcc9-ee2b6f301a6a" xlink:href="glre-20260930.xsd#glre_PerformanceRestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7fbe-9b36-cabfc0e8fb28" xlink:to="loc_glre_PerformanceRestrictedStockMember_01a05da9-2468-7d1c-bcc9-ee2b6f301a6a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ServiceRestrictedStockMember_01a05da9-2468-75d5-a9cf-8c21d5df0882" xlink:href="glre-20260930.xsd#glre_ServiceRestrictedStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7fbe-9b36-cabfc0e8fb28" xlink:to="loc_glre_ServiceRestrictedStockMember_01a05da9-2468-75d5-a9cf-8c21d5df0882" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-729d-a2d1-a50ad6cf84a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-7da0-9c02-cfd1a785e567" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-729d-a2d1-a50ad6cf84a9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_01a05da9-2468-7904-ba54-989091b404fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-729d-a2d1-a50ad6cf84a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_01a05da9-2468-7904-ba54-989091b404fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_01a05da9-2468-79e1-a65b-55a9090752f9" 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-729d-a2d1-a50ad6cf84a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_01a05da9-2468-79e1-a65b-55a9090752f9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_01a05da9-2468-7338-9fd2-b92e4370866b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-729d-a2d1-a50ad6cf84a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_01a05da9-2468-7338-9fd2-b92e4370866b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_01a05da9-2468-7c1b-a987-481c2a2071a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-729d-a2d1-a50ad6cf84a9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_01a05da9-2468-7c1b-a987-481c2a2071a7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_01a05da9-2468-74ea-b2b0-8453b3562d9b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-7103-bac1-7d92f8cccd66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-7da0-9c02-cfd1a785e567" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-7103-bac1-7d92f8cccd66" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_01a05da9-2468-75bf-9593-2754439c4f51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-7103-bac1-7d92f8cccd66" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_01a05da9-2468-75bf-9593-2754439c4f51" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_01a05da9-2468-778f-a424-61e4caf36e3d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-7103-bac1-7d92f8cccd66" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_01a05da9-2468-778f-a424-61e4caf36e3d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_01a05da9-2468-78c1-9a4e-22e315d24048" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-7103-bac1-7d92f8cccd66" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_01a05da9-2468-78c1-9a4e-22e315d24048" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_01a05da9-2468-7333-a57e-90400341d017" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-7103-bac1-7d92f8cccd66" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_01a05da9-2468-7333-a57e-90400341d017" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_01a05da9-2468-740d-a61e-9a8178ae30e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/SHAREBASEDCOMPENSATIONScheduleofRestrictedStockUnitsDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#SHAREBASEDCOMPENSATIONScheduleofRestrictedStockUnitsDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/SHAREBASEDCOMPENSATIONScheduleofRestrictedStockUnitsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-7e5b-ab3f-d76c4bd3ccb1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7b5e-941f-f9841c49ab16" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-7e5b-ab3f-d76c4bd3ccb1" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7b5e-941f-f9841c49ab16" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_01a05da9-2468-7d0a-9e3e-21b4778d8cef" 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_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_01a05da9-2468-7b5e-941f-f9841c49ab16" xlink:to="loc_us-gaap_AwardTypeAxis_01a05da9-2468-7d0a-9e3e-21b4778d8cef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7d0a-9e3e-21b4778d8cef_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_01a05da9-2468-7d0a-9e3e-21b4778d8cef" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7d0a-9e3e-21b4778d8cef_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7e71-9c46-812b43883ad6" 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_01a05da9-2468-7d0a-9e3e-21b4778d8cef" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7e71-9c46-812b43883ad6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_PerformanceRestrictedStockUnitsMember_01a05da9-2468-7fa0-bd3e-f6b40e7b9dbe" xlink:href="glre-20260930.xsd#glre_PerformanceRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7e71-9c46-812b43883ad6" xlink:to="loc_glre_PerformanceRestrictedStockUnitsMember_01a05da9-2468-7fa0-bd3e-f6b40e7b9dbe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ServiceRestrictedStockUnitsMember_01a05da9-2468-760b-94e7-ad1e05472253" xlink:href="glre-20260930.xsd#glre_ServiceRestrictedStockUnitsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_01a05da9-2468-7e71-9c46-812b43883ad6" xlink:to="loc_glre_ServiceRestrictedStockUnitsMember_01a05da9-2468-760b-94e7-ad1e05472253" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-7ca5-a439-08b7a25dea54" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-7e5b-ab3f-d76c4bd3ccb1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-7ca5-a439-08b7a25dea54" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_01a05da9-2468-7f53-a351-52f9af9a7f46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-7ca5-a439-08b7a25dea54" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_01a05da9-2468-7f53-a351-52f9af9a7f46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_01a05da9-2468-76b0-982a-b5111c61a550" 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-7ca5-a439-08b7a25dea54" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_01a05da9-2468-76b0-982a-b5111c61a550" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_01a05da9-2468-7914-855a-17547c28639d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-7ca5-a439-08b7a25dea54" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_01a05da9-2468-7914-855a-17547c28639d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_01a05da9-2468-73e7-85b6-6d7402803690" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_01a05da9-2468-7ca5-a439-08b7a25dea54" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_01a05da9-2468-73e7-85b6-6d7402803690" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_01a05da9-2468-73da-9584-c7b9e8fac8ea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-70bb-834a-3872e2a5ffcb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_01a05da9-2468-7e5b-ab3f-d76c4bd3ccb1" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-70bb-834a-3872e2a5ffcb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_01a05da9-2468-70a5-8225-e5624e836caa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-70bb-834a-3872e2a5ffcb" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_01a05da9-2468-70a5-8225-e5624e836caa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_01a05da9-2468-7996-a019-223cd6b4af8b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-70bb-834a-3872e2a5ffcb" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_01a05da9-2468-7996-a019-223cd6b4af8b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_01a05da9-2468-7475-864d-93f100c6701c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-70bb-834a-3872e2a5ffcb" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_01a05da9-2468-7475-864d-93f100c6701c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_01a05da9-2468-7a8a-89c3-7433ee4b4283" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_01a05da9-2468-70bb-834a-3872e2a5ffcb" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_01a05da9-2468-7a8a-89c3-7433ee4b4283" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_01a05da9-2468-7dfa-a212-a0febdf7bb5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/EARNINGSPERSHAREDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#EARNINGSPERSHAREDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/EARNINGSPERSHAREDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDilutedLineItems_01a05da9-2468-77c3-9164-57eaf13e86f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDilutedLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable_01a05da9-2468-75a8-9cf3-a239e8a8f9d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EarningsPerShareDilutedLineItems_01a05da9-2468-77c3-9164-57eaf13e86f9" xlink:to="loc_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable_01a05da9-2468-75a8-9cf3-a239e8a8f9d7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_01a05da9-2468-7ed1-a5e7-f014caab9d57" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable_01a05da9-2468-75a8-9cf3-a239e8a8f9d7" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_01a05da9-2468-7ed1-a5e7-f014caab9d57" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_01a05da9-2468-7ed1-a5e7-f014caab9d57_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_01a05da9-2468-7ed1-a5e7-f014caab9d57" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_01a05da9-2468-7ed1-a5e7-f014caab9d57_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_01a05da9-2468-7e2b-aadf-e4f7c6237b0c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_01a05da9-2468-7ed1-a5e7-f014caab9d57" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_01a05da9-2468-7e2b-aadf-e4f7c6237b0c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_01a05da9-2468-7ac2-976f-1f6330d06b15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_01a05da9-2468-7e2b-aadf-e4f7c6237b0c" xlink:to="loc_us-gaap_EmployeeStockOptionMember_01a05da9-2468-7ac2-976f-1f6330d06b15" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_01a05da9-2468-7933-96b0-e0dfd273b1d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareDilutedLineItems_01a05da9-2468-77c3-9164-57eaf13e86f9" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_01a05da9-2468-7933-96b0-e0dfd273b1d3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_01a05da9-2468-768a-bd5c-e33657787c0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_01a05da9-2468-7933-96b0-e0dfd273b1d3" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_01a05da9-2468-768a-bd5c-e33657787c0e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_01a05da9-2468-7275-bb8b-7c90a734b0aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasicAbstract_01a05da9-2468-7933-96b0-e0dfd273b1d3" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_01a05da9-2468-7275-bb8b-7c90a734b0aa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_01a05da9-2468-7cad-85c2-47bab85e4b88" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareDilutedLineItems_01a05da9-2468-77c3-9164-57eaf13e86f9" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_01a05da9-2468-7cad-85c2-47bab85e4b88" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_01a05da9-2468-7725-9a0e-32bdc78f246c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_01a05da9-2468-7cad-85c2-47bab85e4b88" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_01a05da9-2468-7725-9a0e-32bdc78f246c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_01a05da9-2468-7af8-b0d9-01c3915a2ad3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_01a05da9-2468-7cad-85c2-47bab85e4b88" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_01a05da9-2468-7af8-b0d9-01c3915a2ad3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_01a05da9-2468-7ff6-9d64-3b7bce58c2ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_01a05da9-2468-7cad-85c2-47bab85e4b88" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_01a05da9-2468-7ff6-9d64-3b7bce58c2ee" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_01a05da9-2468-7dff-b46b-34b226f44a22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract_01a05da9-2468-7cad-85c2-47bab85e4b88" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_01a05da9-2468-7dff-b46b-34b226f44a22" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_EarningsPerShareAttributableToCommonStockholdersAbstract_01a05da9-2468-78ac-a305-6ddbb9cc9858" xlink:href="glre-20260930.xsd#glre_EarningsPerShareAttributableToCommonStockholdersAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareDilutedLineItems_01a05da9-2468-77c3-9164-57eaf13e86f9" xlink:to="loc_glre_EarningsPerShareAttributableToCommonStockholdersAbstract_01a05da9-2468-78ac-a305-6ddbb9cc9858" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_01a05da9-2468-77c7-86ad-46936b44fc8b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EarningsPerShareAttributableToCommonStockholdersAbstract_01a05da9-2468-78ac-a305-6ddbb9cc9858" xlink:to="loc_us-gaap_EarningsPerShareBasic_01a05da9-2468-77c7-86ad-46936b44fc8b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_01a05da9-2468-7c9c-affa-ecd9595a199a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_glre_EarningsPerShareAttributableToCommonStockholdersAbstract_01a05da9-2468-78ac-a305-6ddbb9cc9858" xlink:to="loc_us-gaap_EarningsPerShareDiluted_01a05da9-2468-7c9c-affa-ecd9595a199a" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/RELATEDPARTYTRANSACTIONSDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#RELATEDPARTYTRANSACTIONSDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/RELATEDPARTYTRANSACTIONSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" 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_01a05da9-2468-7b71-b492-f213415b3c80" 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_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_01a05da9-2468-7b71-b492-f213415b3c80" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_01a05da9-2468-7893-8ca3-e1448887b9cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_01a05da9-2468-7b71-b492-f213415b3c80" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_01a05da9-2468-7893-8ca3-e1448887b9cc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_01a05da9-2468-7893-8ca3-e1448887b9cc_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_01a05da9-2468-7893-8ca3-e1448887b9cc" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_01a05da9-2468-7893-8ca3-e1448887b9cc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_01a05da9-2468-7c07-96fd-6e85e5d4740f" 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_01a05da9-2468-7893-8ca3-e1448887b9cc" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_01a05da9-2468-7c07-96fd-6e85e5d4740f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_InvestmentAdvisoryAgreementMember_01a05da9-2468-75bd-bac9-5cb4b1d711e6" xlink:href="glre-20260930.xsd#glre_InvestmentAdvisoryAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_01a05da9-2468-7c07-96fd-6e85e5d4740f" xlink:to="loc_glre_InvestmentAdvisoryAgreementMember_01a05da9-2468-75bd-bac9-5cb4b1d711e6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AffiliatedEntityMember_01a05da9-2468-7aa6-82bf-142fc974695d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AffiliatedEntityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_01a05da9-2468-7c07-96fd-6e85e5d4740f" xlink:to="loc_srt_AffiliatedEntityMember_01a05da9-2468-7aa6-82bf-142fc974695d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ServiceAgreementMember_01a05da9-2468-7369-b73b-78f838178326" xlink:href="glre-20260930.xsd#glre_ServiceAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_01a05da9-2468-7c07-96fd-6e85e5d4740f" xlink:to="loc_glre_ServiceAgreementMember_01a05da9-2468-7369-b73b-78f838178326" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_CollateralAssetsInvestementManagementAgreementMember_01a05da9-2468-7eba-81c6-e3285c457da2" xlink:href="glre-20260930.xsd#glre_CollateralAssetsInvestementManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_01a05da9-2468-7c07-96fd-6e85e5d4740f" xlink:to="loc_glre_CollateralAssetsInvestementManagementAgreementMember_01a05da9-2468-7eba-81c6-e3285c457da2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_01a05da9-2468-791d-80ed-ff49000b07ee" 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_01a05da9-2468-7b71-b492-f213415b3c80" xlink:to="loc_srt_CounterpartyNameAxis_01a05da9-2468-791d-80ed-ff49000b07ee" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a05da9-2468-791d-80ed-ff49000b07ee_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_01a05da9-2468-791d-80ed-ff49000b07ee" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a05da9-2468-791d-80ed-ff49000b07ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a05da9-2468-741b-890e-618b952ea4f9" 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_01a05da9-2468-791d-80ed-ff49000b07ee" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a05da9-2468-741b-890e-618b952ea4f9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_GreenBricksPartnersIncGRBKMember_01a05da9-2468-753e-b0e6-c82189851dd6" xlink:href="glre-20260930.xsd#glre_GreenBricksPartnersIncGRBKMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_01a05da9-2468-741b-890e-618b952ea4f9" xlink:to="loc_glre_GreenBricksPartnersIncGRBKMember_01a05da9-2468-753e-b0e6-c82189851dd6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis_01a05da9-2468-74b9-8e52-0fe92ef559ca" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LegalEntityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_01a05da9-2468-7b71-b492-f213415b3c80" xlink:to="loc_dei_LegalEntityAxis_01a05da9-2468-74b9-8e52-0fe92ef559ca" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a05da9-2468-74b9-8e52-0fe92ef559ca_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_01a05da9-2468-74b9-8e52-0fe92ef559ca" xlink:to="loc_dei_EntityDomain_01a05da9-2468-74b9-8e52-0fe92ef559ca_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain_01a05da9-2468-7ccd-a53f-67b7e2b082e3" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_01a05da9-2468-74b9-8e52-0fe92ef559ca" xlink:to="loc_dei_EntityDomain_01a05da9-2468-7ccd-a53f-67b7e2b082e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-2468-7b6c-bcd5-f523ade2ba6c" xlink:href="glre-20260930.xsd#glre_SolasglasInvestmentsLPSILPMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_01a05da9-2468-7ccd-a53f-67b7e2b082e3" xlink:to="loc_glre_SolasglasInvestmentsLPSILPMember_01a05da9-2468-7b6c-bcd5-f523ade2ba6c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_01a05da9-2468-7f9f-90da-fd22b344a0fd" 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_01a05da9-2468-7b71-b492-f213415b3c80" xlink:to="loc_srt_OwnershipAxis_01a05da9-2468-7f9f-90da-fd22b344a0fd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a05da9-2468-7f9f-90da-fd22b344a0fd_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_01a05da9-2468-7f9f-90da-fd22b344a0fd" xlink:to="loc_srt_OwnershipDomain_01a05da9-2468-7f9f-90da-fd22b344a0fd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_01a05da9-2468-7725-af0f-b11f6f014fb8" 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_01a05da9-2468-7f9f-90da-fd22b344a0fd" xlink:to="loc_srt_OwnershipDomain_01a05da9-2468-7725-af0f-b11f6f014fb8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_GreenBricksPartnersIncGRBKMember_01a05da9-2468-712c-8349-242aae46489d" xlink:href="glre-20260930.xsd#glre_GreenBricksPartnersIncGRBKMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_01a05da9-2468-7725-af0f-b11f6f014fb8" xlink:to="loc_glre_GreenBricksPartnersIncGRBKMember_01a05da9-2468-712c-8349-242aae46489d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_01a05da9-2468-71af-8145-b303d7f8be83" 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_01a05da9-2468-7b71-b492-f213415b3c80" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_01a05da9-2468-71af-8145-b303d7f8be83" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_01a05da9-2468-71af-8145-b303d7f8be83_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_01a05da9-2468-71af-8145-b303d7f8be83" xlink:to="loc_us-gaap_RelatedPartyDomain_01a05da9-2468-71af-8145-b303d7f8be83_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_01a05da9-2468-751c-8602-a32aabd14fcd" 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_01a05da9-2468-71af-8145-b303d7f8be83" xlink:to="loc_us-gaap_RelatedPartyDomain_01a05da9-2468-751c-8602-a32aabd14fcd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_BoardOfDirectorsChairmanMember_01a05da9-2468-7096-b88e-060d4f93c3d0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_BoardOfDirectorsChairmanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_01a05da9-2468-751c-8602-a32aabd14fcd" xlink:to="loc_srt_BoardOfDirectorsChairmanMember_01a05da9-2468-7096-b88e-060d4f93c3d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-737d-99fd-58418feb83eb" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_01a05da9-2468-7b71-b492-f213415b3c80" xlink:to="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-737d-99fd-58418feb83eb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-737d-99fd-58418feb83eb_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-737d-99fd-58418feb83eb" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-737d-99fd-58418feb83eb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-724e-aecf-b0813e67be2e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-737d-99fd-58418feb83eb" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-724e-aecf-b0813e67be2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OrdinaryShareRepurchaseAgreementMember_01a05da9-2468-7fd1-8f85-9e7e76a8dd76" xlink:href="glre-20260930.xsd#glre_OrdinaryShareRepurchaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-724e-aecf-b0813e67be2e" xlink:to="loc_glre_OrdinaryShareRepurchaseAgreementMember_01a05da9-2468-7fd1-8f85-9e7e76a8dd76" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_DavidMEinhorn202107FamilyTrustRepurchaseAgreementMember_01a168d7-55f7-7c06-8854-41ce9e326d6b" xlink:href="glre-20260930.xsd#glre_DavidMEinhorn202107FamilyTrustRepurchaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-724e-aecf-b0813e67be2e" xlink:to="loc_glre_DavidMEinhorn202107FamilyTrustRepurchaseAgreementMember_01a168d7-55f7-7c06-8854-41ce9e326d6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_RelatedPartyTransactionMonthlyManagementFeePercentage_01a05da9-2468-77eb-9e00-78e9248066d5" xlink:href="glre-20260930.xsd#glre_RelatedPartyTransactionMonthlyManagementFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_glre_RelatedPartyTransactionMonthlyManagementFeePercentage_01a05da9-2468-77eb-9e00-78e9248066d5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_RelatedPartyTransactionAnnualManagementFeePercentage_01a05da9-2468-70eb-b2d5-38064007aa9f" xlink:href="glre-20260930.xsd#glre_RelatedPartyTransactionAnnualManagementFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_glre_RelatedPartyTransactionAnnualManagementFeePercentage_01a05da9-2468-70eb-b2d5-38064007aa9f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_RelatedPartyTransactionInvestmentOwnedPercentage_01a05da9-2468-7634-9f84-833c9983c301" xlink:href="glre-20260930.xsd#glre_RelatedPartyTransactionInvestmentOwnedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_glre_RelatedPartyTransactionInvestmentOwnedPercentage_01a05da9-2468-7634-9f84-833c9983c301" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_RelatedPartyTransactionInvestmentOwnedShares_01a05da9-2468-7fb9-bf00-3b38f500382c" xlink:href="glre-20260930.xsd#glre_RelatedPartyTransactionInvestmentOwnedShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_glre_RelatedPartyTransactionInvestmentOwnedShares_01a05da9-2468-7fb9-bf00-3b38f500382c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_01a05da9-2468-701c-a3a8-632eca2782fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionAmountsOfTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction_01a05da9-2468-701c-a3a8-632eca2782fd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_RelatedPartyTransactionsContractTerminationPriorNoticePeriod_01a05da9-2468-77d1-ad0e-adf6482d6cdd" xlink:href="glre-20260930.xsd#glre_RelatedPartyTransactionsContractTerminationPriorNoticePeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_glre_RelatedPartyTransactionsContractTerminationPriorNoticePeriod_01a05da9-2468-77d1-ad0e-adf6482d6cdd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_01a05da9-2468-7ff3-a03c-e6bac8df35e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_01a05da9-2468-7ff3-a03c-e6bac8df35e2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_ShareRepurchaseAgreementBuybackProvisionOutstandingSharesPercentage_01a05da9-2468-7f5f-beb0-460c3e9ec6b7" xlink:href="glre-20260930.xsd#glre_ShareRepurchaseAgreementBuybackProvisionOutstandingSharesPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_glre_ShareRepurchaseAgreementBuybackProvisionOutstandingSharesPercentage_01a05da9-2468-7f5f-beb0-460c3e9ec6b7" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_01a168d7-55f7-7e55-be2f-a8ad9e0831d1" 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_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_01a168d7-55f7-7e55-be2f-a8ad9e0831d1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_01a168d7-55f7-7c06-b02e-c26ee68275c7" 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_RelatedPartyTransactionLineItems_01a05da9-2468-79e5-80da-f0030c44634c" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_01a168d7-55f7-7c06-b02e-c26ee68275c7" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/SEGMENTREPORTINGScheduleofGrossPremiumsWrittenbyLineofBusinessDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#SEGMENTREPORTINGScheduleofGrossPremiumsWrittenbyLineofBusinessDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/SEGMENTREPORTINGScheduleofGrossPremiumsWrittenbyLineofBusinessDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" 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_01a05da9-2468-7c83-b97a-6af8aa046837" 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_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_01a05da9-2468-7c83-b97a-6af8aa046837" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_01a05da9-2468-7f5d-af60-03839ed7d4d8" 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_01a05da9-2468-7c83-b97a-6af8aa046837" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_01a05da9-2468-7f5d-af60-03839ed7d4d8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a05da9-2468-7f5d-af60-03839ed7d4d8_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_01a05da9-2468-7f5d-af60-03839ed7d4d8" xlink:to="loc_us-gaap_SegmentDomain_01a05da9-2468-7f5d-af60-03839ed7d4d8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_01a05da9-2468-7756-b6f0-a04bd012f701" 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_01a05da9-2468-7f5d-af60-03839ed7d4d8" xlink:to="loc_us-gaap_SegmentDomain_01a05da9-2468-7756-b6f0-a04bd012f701" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_OpenMarketMember_01a05da9-2468-78bc-af65-a38521442e94" xlink:href="glre-20260930.xsd#glre_OpenMarketMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a05da9-2468-7756-b6f0-a04bd012f701" xlink:to="loc_glre_OpenMarketMember_01a05da9-2468-78bc-af65-a38521442e94" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_InnovationsMember_01a05da9-2468-7a5f-8775-d454806c9e9c" xlink:href="glre-20260930.xsd#glre_InnovationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_01a05da9-2468-7756-b6f0-a04bd012f701" xlink:to="loc_glre_InnovationsMember_01a05da9-2468-7a5f-8775-d454806c9e9c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_01a05da9-2468-7d10-bc91-678f00f36df6" 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_01a05da9-2468-7c83-b97a-6af8aa046837" xlink:to="loc_srt_ConsolidationItemsAxis_01a05da9-2468-7d10-bc91-678f00f36df6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a05da9-2468-7d10-bc91-678f00f36df6_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_01a05da9-2468-7d10-bc91-678f00f36df6" xlink:to="loc_srt_ConsolidationItemsDomain_01a05da9-2468-7d10-bc91-678f00f36df6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_01a05da9-2468-7771-b555-09d3d3d81e65" 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_01a05da9-2468-7d10-bc91-678f00f36df6" xlink:to="loc_srt_ConsolidationItemsDomain_01a05da9-2468-7771-b555-09d3d3d81e65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_01a05da9-2468-7686-b3b3-b06f386b9be4" 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_01a05da9-2468-7771-b555-09d3d3d81e65" xlink:to="loc_us-gaap_OperatingSegmentsMember_01a05da9-2468-7686-b3b3-b06f386b9be4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_01a05da9-2468-7270-b7ed-5b9a0791d180" 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_01a05da9-2468-7771-b555-09d3d3d81e65" xlink:to="loc_us-gaap_CorporateNonSegmentMember_01a05da9-2468-7270-b7ed-5b9a0791d180" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssumedPremiumsWritten_01a05da9-2468-7cc7-8075-0a0bb6d663a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssumedPremiumsWritten"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_AssumedPremiumsWritten_01a05da9-2468-7cc7-8075-0a0bb6d663a6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PremiumsWrittenNet_01a05da9-2468-7471-bd1d-1785bcb6b8a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PremiumsWrittenNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_PremiumsWrittenNet_01a05da9-2468-7471-bd1d-1785bcb6b8a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PremiumsEarnedNet_01a05da9-2468-7df6-8e54-7845f2facbb4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PremiumsEarnedNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_PremiumsEarnedNet_01a05da9-2468-7df6-8e54-7845f2facbb4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderBenefitsAndClaimsIncurredNet_01a05da9-2468-7122-9d53-b9f79278e07b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PolicyholderBenefitsAndClaimsIncurredNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_PolicyholderBenefitsAndClaimsIncurredNet_01a05da9-2468-7122-9d53-b9f79278e07b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense_01a05da9-2468-75e3-af16-9434a79af35b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense_01a05da9-2468-75e3-af16-9434a79af35b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherUnderwritingExpense_01a05da9-2468-7366-b8da-6fdd8365d8d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherUnderwritingExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_OtherUnderwritingExpense_01a05da9-2468-7366-b8da-6fdd8365d8d4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_InterestIncomeExpenseDepositsNet_01a05da9-2468-74c7-be15-49558be8fc5e" xlink:href="glre-20260930.xsd#glre_InterestIncomeExpenseDepositsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_glre_InterestIncomeExpenseDepositsNet_01a05da9-2468-74c7-be15-49558be8fc5e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnderwritingIncomeLoss_01a05da9-2468-7eb7-98af-09f66179c97c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnderwritingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_UnderwritingIncomeLoss_01a05da9-2468-7eb7-98af-09f66179c97c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetInvestmentIncome_01a05da9-2468-709c-8d70-be5b8ed75ce5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetInvestmentIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_NetInvestmentIncome_01a05da9-2468-709c-8d70-be5b8ed75ce5" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherExpenses_01a05da9-2468-7bc6-906a-d25675617773" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_OtherExpenses_01a05da9-2468-7bc6-906a-d25675617773" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_01a05da9-2468-7098-a92b-725d8728d4f5" 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_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_01a05da9-2468-7098-a92b-725d8728d4f5" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_01a05da9-2468-74d1-9a19-ff962de09ca6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_01a05da9-2468-74d1-9a19-ff962de09ca6" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherOperatingIncomeExpenseNet_01a05da9-2468-7454-96a7-d896b2f9c3bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherOperatingIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_OtherOperatingIncomeExpenseNet_01a05da9-2468-7454-96a7-d896b2f9c3bf" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseOther_01a05da9-2468-7e70-a780-21f79aafb874" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_InterestExpenseOther_01a05da9-2468-7e70-a780-21f79aafb874" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest_01a05da9-2468-7a74-b02d-40785a047c4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest_01a05da9-2468-7a74-b02d-40785a047c4e" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAttritionalLosses_01a05da9-2468-7d4b-95e6-7fdfea727ee1" xlink:href="glre-20260930.xsd#glre_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAttritionalLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_glre_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAttritionalLosses_01a05da9-2468-7d4b-95e6-7fdfea727ee1" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_LargeEventRecoveries_01a18dad-61da-798b-b196-8de629d258b9" xlink:href="glre-20260930.xsd#glre_LargeEventRecoveries"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_glre_LargeEventRecoveries_01a18dad-61da-798b-b196-8de629d258b9" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_RecoveriesFromCatastrophes_01a18dad-d5c7-7ded-8710-a51c6d0e6091" xlink:href="glre-20260930.xsd#glre_RecoveriesFromCatastrophes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_glre_RecoveriesFromCatastrophes_01a18dad-d5c7-7ded-8710-a51c6d0e6091" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_LargeEventLosses_01a05da9-2468-7391-aa4c-97aa74d4a33c" xlink:href="glre-20260930.xsd#glre_LargeEventLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_glre_LargeEventLosses_01a05da9-2468-7391-aa4c-97aa74d4a33c" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LossFromCatastrophes_01a05da9-2468-7491-b00c-7289a6bb5e3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossFromCatastrophes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_LossFromCatastrophes_01a05da9-2468-7491-b00c-7289a6bb5e3e" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_01a05da9-2468-7a0f-8099-548447793287" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense_01a05da9-2468-7a0f-8099-548447793287" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PolicyholderBenefitsAndClaimsIncurredNet_01a05da9-2468-7019-9585-909f339caacf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PolicyholderBenefitsAndClaimsIncurredNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_01a05da9-2468-7ba1-8bfa-ad3f45834222" 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_01a05da9-2468-7482-bd35-5bd0708d3e13" xlink:to="loc_us-gaap_Assets_01a05da9-2468-7ba1-8bfa-ad3f45834222" xlink:type="arc" order="22"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.greenlightre.ky/role/SUBSEQUENTEVENTSDetails" xlink:type="simple" xlink:href="glre-20260930.xsd#SUBSEQUENTEVENTSDetails"/>
  <link:definitionLink xlink:role="http://www.greenlightre.ky/role/SUBSEQUENTEVENTSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_01a05da9-2468-7660-951f-661ae4b7585d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_01a05da9-2468-7dd4-b716-0fc5772c425a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_01a05da9-2468-7660-951f-661ae4b7585d" xlink:to="loc_us-gaap_SubsequentEventTable_01a05da9-2468-7dd4-b716-0fc5772c425a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_01a09ddf-ce1e-7992-9c43-a192d6981671" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_01a05da9-2468-7dd4-b716-0fc5772c425a" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_01a09ddf-ce1e-7992-9c43-a192d6981671" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a09ddf-ce1e-7992-9c43-a192d6981671_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_01a09ddf-ce1e-7992-9c43-a192d6981671" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a09ddf-ce1e-7992-9c43-a192d6981671_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_01a09ddf-ce1e-7dbb-98d5-987b97504554" 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_01a09ddf-ce1e-7992-9c43-a192d6981671" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_01a09ddf-ce1e-7dbb-98d5-987b97504554" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_01a09ddf-ce1e-7bb4-996a-27455491b3ef" 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_01a09ddf-ce1e-7dbb-98d5-987b97504554" xlink:to="loc_us-gaap_SubsequentEventMember_01a09ddf-ce1e-7bb4-996a-27455491b3ef" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-7363-bb11-3057b2a81cc1" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_01a05da9-2468-7dd4-b716-0fc5772c425a" xlink:to="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-7363-bb11-3057b2a81cc1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-7363-bb11-3057b2a81cc1_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-7363-bb11-3057b2a81cc1" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-7363-bb11-3057b2a81cc1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-7221-b263-8ffdb08c7726" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ShareRepurchaseProgramAxis_01a05da9-2468-7363-bb11-3057b2a81cc1" xlink:to="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-7221-b263-8ffdb08c7726" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_glre_DavidMEinhorn202107FamilyTrustRepurchaseAgreementMember_01a05da9-2468-7384-bc6a-9f0af1133dbb" xlink:href="glre-20260930.xsd#glre_DavidMEinhorn202107FamilyTrustRepurchaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ShareRepurchaseProgramDomain_01a05da9-2468-7221-b263-8ffdb08c7726" xlink:to="loc_glre_DavidMEinhorn202107FamilyTrustRepurchaseAgreementMember_01a05da9-2468-7384-bc6a-9f0af1133dbb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_01a05da9-2468-77f6-ab3d-857de653f753" 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_SubsequentEventLineItems_01a05da9-2468-7660-951f-661ae4b7585d" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_01a05da9-2468-77f6-ab3d-857de653f753" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_01a05da9-2468-798d-a18d-79e9c380010e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_01a05da9-2468-7660-951f-661ae4b7585d" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_01a05da9-2468-798d-a18d-79e9c380010e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_01a05da9-2468-7e56-b586-3b339aef5c2b" 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_SubsequentEventLineItems_01a05da9-2468-7660-951f-661ae4b7585d" xlink:to="loc_us-gaap_TreasuryStockAcquiredAverageCostPerShare_01a05da9-2468-7e56-b586-3b339aef5c2b" xlink:type="arc" order="2"/>
  </link:definitionLink>
</link:linkbase>
