'Exogamy' definitions:

Definition of 'exogamy'

From: WordNet
noun
Marriage to a person belonging to a tribe or group other than your own as required by custom or law [syn: exogamy, intermarriage] [ant: endogamy, inmarriage, intermarriage]

Definition of 'Exogamy'

From: GCIDE
  • Exogamy \Ex*og"a*my\, n. The custom, or tribal law, which prohibits marriage between members of the same tribe; marriage outside of the tribe; -- opposed to endogamy. --Lubbock. [1913 Webster]