'aplacophoran' originates from New Latin, specifically the word 'Aplacophora', where 'a-' meant 'not', 'plakos' (Greek) meant 'plate', and 'phorein' (Greek) meant 'to bear'.

'aplacophoran' developed from the scientific New Latin name 'Aplacophora' (used for the class of mollusks) and was adopted into English as the noun/adjective 'aplacophoran' to describe members of that group.

Initially the roots referred to 'not bearing plates' (literally 'without plates'), and over time the term came to denote the specific group of shell-less, worm-like mollusks classified as Aplacophora.