means A social group bound together by shared ancestry, customs, language, or allegiance, often forming a distinct community within a larger society.

from From Latin 'tribus', the name for the three original divisions of the Roman people — and possibly built from 'tri-' (three) plus a root tied to 'bhū-', to be or grow. The Romans split their citizenry into these tribus for voting and taxation, and the word later widened far beyond Rome to name any people knit by blood and custom. The same root quietly survives in 'tribute' (what the tribes paid) and 'tribunal' (where the tribes were judged).