'invertebrate' originates from Latin, specifically the word 'invertebratus,' where 'in-' meant 'not' and 'vertebratus' meant 'jointed or having vertebrae.'

'invertebratus' transformed into the French word 'invertébré,' and eventually became the modern English word 'invertebrate' through Middle English.

Initially, it meant 'not having vertebrae,' and this meaning has largely remained the same in modern usage.