water boatman

from WordNet (r) 3.0 (2006)

water boatman
    n 1: carnivorous aquatic bug having paddle-like hind legs [syn:
         {water boatman}, {boat bug}]

from The Collaborative International Dictionary of English v.0.48

Water boatman \Wa"ter boat`man\ (Zool.)
   A boat bug.
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Boat bug \Boat" bug`\ (Zool.)
   An aquatic hemipterous insect of the genus {Notonecta}; -- so
   called from swimming on its back, which gives it the
   appearance of a little boat. Called also {boat fly}, {boat
   insect}, {boatman}, and {water boatman}.
   [1913 Webster]

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