'aphyllous' originates from New Latin, ultimately from Greek 'aphyllos', where the prefix 'a-' meant 'without' and 'phyll-' (from 'phyllon') meant 'leaf'.

'aphyllos' (Greek) combined 'a-' + 'phyllon' to mean 'without leaves'; it entered New Latin as 'aphyllus/aphyllos' and was adapted into English as 'aphyllous'.

Initially it meant 'without leaves' in botanical contexts, and it has retained this specialized meaning in modern usage.