In the U.S., any of the pit vipers such as the copperhead, water moccasin, and rattlesnake of the family Crotalidae, and, in the southern U.S, the coral snakes (genus Micrurus) , especially M. fulvius and M. euryxanthus. Venomous snakes have a worldwide distribution. Specific names of snakes in the general vocabulary are listed under the first word.