The Collaborative International Dictionary of English v.0.48:

Tenaculum \Te*nac"u*lum\, n.; pl. L. Tenacula; E.
   Tenaculums. [L., a holder, fr. tenere to hold. Cf.
   Tenaille.] (Surg.)
   An instrument consisting of a fine, sharp hook attached to a
   handle, and used mainly for taking up arteries, and the like.
   [1913 Webster]