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

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019ff12b-e339-7761-9d68-3fc2e4b93555,g:55ad9aa7-c5d2-4fe5-b6ee-530f7916dcde-->
<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.lgihomes.com/role/CoverPageCoverPage" xlink:type="simple" xlink:href="lgih-20261103.xsd#CoverPageCoverPage"/>
  <link:definitionLink xlink:role="http://www.lgihomes.com/role/CoverPageCoverPage" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsLineItems_019ff12b-e339-7f11-be4a-3785e22a0bd3" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityListingsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsTable_019ff12b-e339-729c-8069-eefda83aa39c" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityListingsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityListingsLineItems_019ff12b-e339-7f11-be4a-3785e22a0bd3" xlink:to="loc_dei_EntityListingsTable_019ff12b-e339-729c-8069-eefda83aa39c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsExchangeAxis_019ff12b-e339-7413-9beb-e6c7d8b931ea" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityListingsExchangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntityListingsTable_019ff12b-e339-729c-8069-eefda83aa39c" xlink:to="loc_dei_EntityListingsExchangeAxis_019ff12b-e339-7413-9beb-e6c7d8b931ea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_019ff12b-e339-7413-9beb-e6c7d8b931ea_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_EntityListingsExchangeAxis_019ff12b-e339-7413-9beb-e6c7d8b931ea" xlink:to="loc_dei_ExchangeDomain_019ff12b-e339-7413-9beb-e6c7d8b931ea_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_019ff12b-e339-7e03-9934-d25c024dd94f" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_EntityListingsExchangeAxis_019ff12b-e339-7413-9beb-e6c7d8b931ea" xlink:to="loc_dei_ExchangeDomain_019ff12b-e339-7e03-9934-d25c024dd94f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exch_XNGS_019ff12b-e339-7617-ac98-f652aa136712" xlink:href="https://xbrl.sec.gov/exch/2026/exch-2026.xsd#exch_XNGS"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_ExchangeDomain_019ff12b-e339-7e03-9934-d25c024dd94f" xlink:to="loc_exch_XNGS_019ff12b-e339-7617-ac98-f652aa136712" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_lgih_Exch_NasdaqTexasLLCMember_019ff12b-e339-782a-8bda-a2cd03b198d7" xlink:href="lgih-20261103.xsd#lgih_Exch_NasdaqTexasLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_ExchangeDomain_019ff12b-e339-7e03-9934-d25c024dd94f" xlink:to="loc_lgih_Exch_NasdaqTexasLLCMember_019ff12b-e339-782a-8bda-a2cd03b198d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019ff12b-e339-7fff-a518-99e25793e467" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityListingsLineItems_019ff12b-e339-7f11-be4a-3785e22a0bd3" xlink:to="loc_dei_SecurityExchangeName_019ff12b-e339-7fff-a518-99e25793e467" xlink:type="arc" order="0"/>
  </link:definitionLink>
</link:linkbase>
