Viperoidea \Vi`per*oi"de*a\, Viperoides \Vi`per*oi"des\, n. pl. [NL. See {Viper}, and {-oid}.] (Zo["o]l.) A division of serpents which includes the true vipers of the Old World and the rattlesnakes and moccasin snakes of America; -- called also {Viperina}.