Word Study
cottonmouth
CIDE DICTIONARY
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. [WordNet 1.5]
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