hippa

from The Collaborative International Dictionary of English v.0.48

Hippa \Hip"pa\, Hippe \Hip"pe\, n. (Zool.)
   A genus of marine decapod crustaceans, which burrow rapidly
   in the sand by pushing themselves backward; -- called also
   {bait bug}. See Illust. under {Anomura}.
   [1913 Webster]