Tre‐pan″ (?), n. [F. trépan (cf. Sp. trépano, It. trepano, trapano), LL. trepanum, fr. Gr. � a borer, auger, trepan, fr. � to bore, � a hole. Cf. Trephine.] 1. (Surg.) A crown-saw or cylindrical saw for perforating the skull, turned, when used, like a bit or gimlet. See Trephine.
2. (Mining) A kind of broad chisel for sinking shafts.