Source : Webster's Revised Unabridged Dictionary (1913)

Endogamous \En*dog"a*mous\, a. [Endo- + Gr. ? marriage.]
   Marrying within the same tribe; -- opposed to exogamous.

Source : WordNet®

endogamous
     adj 1: characterized by or fit for fertilization by pollen from
            another flower of the same kind [syn: {endogamic}]
            [ant: {exogamous}, {autogamous}]
     2: pertaining to or characterized by the custom of marrying
        only within the limits of a clan or tribe [syn: {endogamic}]
        [ant: {exogamous}]