'assimilant' originates from Latin, specifically the word 'assimilare,' where 'ad-' meant 'toward' and 'similis' meant 'like or similar.'

'assimilare' transformed into the French word 'assimiler,' and eventually became the modern English word 'assimilant' through Middle English.

Initially, it meant 'to make similar or to absorb,' and this meaning has largely remained the same in modern usage.