Viper

Webster's Practical Dictionary- A Practical Dictionary of the Englih Language · 1884 · p. 503

vi'per,n. A poisonous serpent of several species; any venomous snake; a malignant person.— Vi'penne, -in, a. to, etc.— viper, Of, or pert, Vi'perous, -us, a. Having the qualities of a viper; malignant; venomous.