Lewis & Short

narthēcĭum, ii, n., = ναρθήκιον (lit. a piece of narthex-wood which has been hollowed out for keeping ointments and medicines in; hence any vessel in which these articles are kept), an ointment-box, a medicine-chest, Mart. 14, 78, 1: jam doloris medicamenta illa Epicurea tamquam de narthecio proment, Cic. Fin. 2, 7, 22.