tribe

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A unit of sociopolitical organization consisting of a number of families, clans, or other groups who share a common ancestry and culture and among whom leadership is typically neither formalized nor permanent.
• noun A political, ethnic, or ancestral division of ancient states and cultures, especially.
• noun Any of the three divisions of the ancient Romans, namely, the Latin, Sabine, and Etruscan.
• noun Any of the 12 divisions of ancient Israel.
• noun A phyle of ancient Greece.
• noun A group of people sharing an occupation, interest, or habit.
• noun Informal A large family.
• noun Biology A taxonomic category ranking below a family or subfamily and above a genus and usually containing several genera.

from The Century Dictionary.

• To distribute into tribes or classes.
• noun In Roman history, one of the three patrician orders, or original political divisions of the people of ancient Rome, the Ramnes, Tities, and Luceres, representing respectively, according to tradition, the separate Latin, Sabine, and Etruscan settlements, having at their union equal representation in the senate, and retaining their distinctive names for several centuries.
• noun Any one of the similar divisions of a race or nation common in antiquity, whether of natural or of political origin: as, the tribes (φυλαι) of Athens.
• noun Specifically, a division of a barbarous race of people, usually distinguishable in some way from their congeners, united into a community under a recognized head or chief, ruling either independently or subordinately.
• noun Any class or body of persons taken collectively; any aggregate of individuals of a kind, either as a united body or as distinguished by some common characteristic or occupation.
• noun A family of cattle having a common female ancestor.
• noun In zoology and botany, a classificatory group of uncertain taxonomic rank, above a genus, and usually below an order; loosely, any group or series of animals: as, the furry, feathery, or finny tribes; the cat tribe.

from the GNU version of the Collaborative International Dictionary of English.

• transitive verb rare To distribute into tribes or classes.
• noun A family, race, or series of generations, descending from the same progenitor, and kept distinct, as in the case of the twelve tribes of Israel, descended from the twelve sons of Jacob.
• noun (Bot.) A number of species or genera having certain structural characteristics in common.
• noun A nation of savages or uncivilized people; a body of rude people united under one leader or government.
• noun A division, class, or distinct portion of a people, from whatever cause that distinction may have originated.
• noun (Stock Breeding) A family of animals descended from some particular female progenitor, through the female line.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A socially, ethnically, and politically cohesive group of people.
• noun anthropology A society larger than a band but smaller than a state.
• noun The collective noun for various animals.
• noun taxonomy A hierarchal rank between family and genus.
• verb transitive To distribute into tribes or classes; to categorize.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun (biology) a taxonomic category between a genus and a subfamily
• noun a social division of (usually preliterate) people
• noun a federation (as of American Indians)
• noun group of people related by blood or marriage