[1] : The Collaborative International Dictionary of English v.0.48

backswimmer \back"swim`mer\ n.
   any of numerous predaceous aquatic insects of the family
   notonectidae such as notonecta undulata that swim on
   their backs and may inflict painful bites; -- also called
   boat bug. --rhud
   wordnet 1.5 +pjc
see also:
notonectidae notonecta undulata boat bug 

[2] : 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
see also:
notonecta boat fly boat insect boatman water boatman 

[3] : WordNet (r) 2.0

boat bug
     n : carnivorous aquatic bug having paddle-like hind legs syn: water
         boatman
see also:
water boatman 

Bug >> B Words
Bug, definition of term: Bug
bug_pag1.html

Boat >> B Words
Boat, definition of term: Boat
boat_pag1.html

Bug Out >> B Words
Bug Out, definition of term: Bug Out
bug+out_pag1.html

Bed Bug >> B Words
Bed Bug, definition of term: Bed Bug
bed+bug_pag1.html