I disagree with "city" and "household" but agree with "tribe". A city is a fixed location and can also mean a "collection of buildings" - eg. a "deserted city". A household also pertains to a building (no household without a house). A tribe is much looser in terms of geography, eg. "a tribe of nomads". A colony of ants is potentially mobile or fixed - the OED validates both. Colony is also cited as a valid collective noun for a number of other animals. It doesn't have to be the dominant usage, only a permissible one - MMGB |