cystotome

from The Collaborative International Dictionary of English v.0.48

Cystotome \Cys"to*tome\ (s?s"t?-t?m), n. [Gr. ??? bladder + ????
   to cut: cf. F. cystotome.] (Surg.)
   A knife or instrument used in cystotomy.
   [1913 Webster]