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]