'caterpillar' originates from Old French, specifically the word 'catepelose,' where 'cate-' meant 'cat' and 'pelose' meant 'hairy.'

'catepelose' transformed into the Middle English word 'catirpel,' and eventually became the modern English word 'caterpillar.'

Initially, it meant 'hairy cat,' but over time it evolved into its current meaning of 'larval stage of a butterfly or moth.'