Viper(a.) Any one of numerous species of Old World venomous makes belonging to Vipera, Clotho, Daboia, and other genera of the family Viperidae.
Viper(a.) A dangerous, treacherous, or malignant person.
Viperous(a.) Having the qualities of a viper; malignant; venomous; as, a viperous tongue.

Words within viperously