'allotropy' originates from Greek, specifically the word 'allotropos,' where 'allo-' meant 'other' and 'tropos' meant 'way or manner.'

'allotropos' transformed into the French word 'allotropie,' and eventually became the modern English word 'allotropy' through Middle English.

Initially, it meant 'other manner or form,' and this meaning has largely remained the same in modern usage.