'docetist' originates from Greek, specifically the word 'dokein', where 'dokein' meant 'to seem'.

'docetist' entered English via Late Latin/Medieval Latin and French (e.g. Latin 'docetismus' / French 'docétisme') describing the doctrine, and was adopted into English as 'docetist' to name an adherent of that doctrine.

Initially, the root referred more generally to 'seeming' or 'appearing'; over time the term became specialized to denote an adherent of the theological position that Christ's physical reality was only apparent.