c.1520, from M.Fr.
vipere, from L.
vipera "viper, snake, serpent," from
vivus "alive, living" (see
vital) +
parere "bring forth, bear" (see
pare). It formerly was believed (mistakenly) that the viper does not lay eggs. Applied to persons of spiteful character since at least 1591. The only venomous snake found in Great Britain. Replaced native
adder. "The flesh of the viper was formerly regarded as possessing great nutritive or restorative properties, and was frequently used medicinally" [OED]; hence
viper wine, wine medicated with some kind of extract from vipers, used 17c. by "gray-bearded gallants" in a bid "to feele new lust, and youthfull flames agin."