'allotropism' originates from Greek, specifically the word 'allotropos,' where 'allo-' meant 'other' and 'tropos' meant 'form.'

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

Initially, it meant 'other form,' but over time it evolved into its current meaning of 'the property of elements to exist in different forms.'