'commonly-divided' originates from the combination of 'common' and 'divide,' where 'common' meant 'usual' and 'divide' meant 'to separate.'

'commonly-divided' changed from the Old English word 'cumman' (common) and Latin 'dividere' (divide) and eventually became the modern English word 'commonly-divided'.

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