'equally-divided' originates from the combination of 'equal' and 'divide', where 'equal' comes from Latin 'aequalis' meaning 'even, level' and 'divide' from Latin 'dividere' meaning 'to separate'.

'equally-divided' evolved from the Middle English 'equale' and 'dividen', eventually forming the modern English term 'equally-divided'.

Initially, it meant 'to separate into equal parts', and this meaning has largely remained the same in modern usage.