/kot"n mowth'/ , n. , pl. cottonmouths /-mowths', -mowdhz'/ .
a venomous snake, Agkistrodon ( Ancistrodon ) piscivorus, of swamps in southeastern U.S., that grows to about 4 ft. (1.2 m). Also called water moccasin .
[ 1825-35, Amer.; COTTON + MOUTH, so called from the whiteness of its lips and mouth ]