vicious
adjectiveMean-spirited or deliberately hurtful; malicious.
adjectiveExtremely violent or injurious; cruel.
adjectiveMarked by an aggressive disposition. Used chiefly of animals.
adjectiveDisposed to violent or destructive behavior.
adjectiveSevere, powerful, or intense; fierce.
adjectiveHaving the nature of vice; evil, immoral, or depraved.
adjectiveGiven to vice, immorality, or depravity.
adjectiveFaulty or defective.