noun

1. esp. among preliterate peoples, a group of persons, families, or clans believed to be descended from a common ancestor and forming a close community under a leader, or chief
2. a group of this kind having recognized ancestry; specif.,
   1. any of the three divisions of the ancient Romans, traditionally of Latin, Sabine, and Etruscan origin
   2. any of the later political and territorial divisions of the ancient Romans
   3. any of the phylae of ancient Greece
   4. any of the twelve divisions of the ancient Israelites
3. any group of people having the same occupation, habits, ideas, etc.: often in a somewhat derogatory sense the tribe of drama critics
4. a taxonomic category that is a subdivision of a subfamily of plants or animals and consists of several closely related genera
5. a natural group of plants or animals classified together without regard for their taxonomic relations
6. in stock breeding, the animals descended from the same female through the female line
7. Informal a family, esp. a large one

Etymology: ME trybe < L tribus, one of the three groups into which Romans were orig. divided, tribe < tri- (see tri-) + IE *bhū- < base *bheu-, to grow, flourish > be