The Collaborative International Dictionary of English v.0.48:

Terebra \Ter"e*bra\, n.; pl. E. Terebras, L. Terebrae. [L.,
   a borer.]
   1. (Zool.) A genus of marine gastropods having a long,
      tapering spire. They belong to the Toxoglossa. Called also
      auger shell.
      [1913 Webster]

   2. (Zool.) The boring ovipositor of a hymenopterous insect.
      [1913 Webster]