cottonmouth moccasin

from WordNet (r) 3.0 (2006)

cottonmouth moccasin
    n 1: venomous semiaquatic snake of swamps in southern United
         States [syn: {water moccasin}, {cottonmouth}, {cottonmouth
         moccasin}, {Agkistrodon piscivorus}]

from The Collaborative International Dictionary of English v.0.48

cottonmouth \cottonmouth\ n.
   venomous semiaquatic snake ({Agkistrodon piscivorus}) of
   swamps in southern U.S.; -- called also {water moccasin},
   {cottonmouth moccasin}, and {cottonmouth water moccasin}. It
   grows to a length of about 4 feet. The name refers to the
   whiteness of the lips and inside of the mouth.

   Syn: water moccasin, cottonmouth moccasin, {Agkistrodon
        piscivorus}.
        [WordNet 1.5 +PJC]