viper

Any of various venomous snakes of the family Viperidae, having a thick heavy body and a single pair of long hollow fangs, especially the Eurasian and African species of the subfamily Viperinae, which lack the sensory pits of the pit vipers.

Any of several harmless snakes sometimes believed to be venomous.

A person regarded as malicious or treacherous.

A venomous snake of the family Viperidæ: originally and especially applied to the only serpent of this kind occurring in the greater part of Europe, Vipera communis Or Pelias beruts.

Any venomous serpent except a rattlesnake; a viperine; a cobriform and not crotali form serpent, as a cobra, asp, or adder; also, loosely, any serpent that is venomous, or supposed to be so; a dangerous, repulsive, or ugly snake.