Water moccasin \Wa"ter moc"ca*sin\ (Zool.) A venomous North American snake ({Ancistrodon piscivorus}) allied to the rattlesnake but destitute of a rattle. It lives in or about pools and ponds, and feeds largely of fishes. Called also {water snake}, {water adder}, {water viper}. [1913 Webster]
Water viper \Wa"ter vi"per\ (Zool.) See {Water moccasin}. [1913 Webster]