ENDOGAMY
endogamy, intermarriage, inmarriage
(noun) marriage within one’s own tribe or group as required by custom or law
Source: WordNet® 3.1
Etymology
Noun
endogamy (usually uncountable, plural endogamies)
The practice of marrying or requiring to marry within one's own ethnic, religious, or social group.
(biology) the fusion of two related gametes.
Synonyms
• See also intermarriage
Antonyms
• exogamy
• See also intermarriage
Source: Wiktionary
En*dog"a*my, n.
Definition: Marriage only within the tribe; a custom restricting a man in
his choice of a wife to the tribe to which he belongs; -- opposed to
exogamy.
Source: Webster’s Unabridged Dictionary 1913 Edition