'usually-divided' originates from the combination of 'usually' and 'divided', where 'usually' means 'in most cases' and 'divided' means 'separated into parts'.

The phrase 'usually-divided' combines the adverb 'usually' with the past participle 'divided', forming a compound adjective.

Initially, it meant 'commonly separated into parts', and this meaning has largely remained the same in modern usage.