'apetala' originates from New Latin (botanical Latin), ultimately from Greek components, where the prefix 'a-' meant 'without' and Greek 'petalon' meant 'leaf, petal'.

'apetala' was formed in New Latin from Greek roots (e.g. 'apétalos' / 'a-' + 'petalon') and was adopted into English botanical vocabulary with the same form to describe plants lacking petals.

Initially, it meant 'without petals' in botanical/New Latin contexts, and that core meaning has been retained in modern English botanical usage.