'Tribe' is Latin 'tribus' — one of Rome's three original divisions. Extended through the Vulgate to all peoples.
A social group consisting of families or communities linked by social, economic, religious, or blood ties, with a common culture and dialect, typically having a recognized leader.
From Old French 'tribu,' from Latin 'tribus,' one of the three original divisions of the Roman people (Ramnes, Tities, and Luceres). The etymology of 'tribus' is debated but traditionally connected to 'trēs' (three), reflecting the tripartite division of early Roman society. An alternative theory links it to the root *treb- (dwelling, settlement), seen in Old Irish 'treb' (dwelling) and