'achaenocarp' originates from Greek, specifically the word 'akaina,' where 'a-' meant 'not' and 'kainos' meant 'new,' combined with 'karpos' meaning 'fruit.'

'akaina' transformed into the Latin word 'achaenocarpus,' and eventually became the modern English word 'achaenocarp.'

Initially, it meant 'a fruit that does not open,' and this meaning has largely remained the same in modern usage.