n.1 any venomous snake of the family Viperidae, esp. the common viper (see ADDER).
2 a malignant or treacherous person.
Phrases and idioms:
viper in one's bosom a person who betrays those who have helped him or her. viper's bugloss a stiff bristly blue-flowered plant, Echium vulgare. viper's grass scorzonera.
Derivatives:
viperine adj. viperish adj. viper-like adj. viperous adj.
Etymology: F vip{egrave}re or L vipera f. vivus alive + parere bring forth