Pronunciation: (vish'us),[key] —adj. 1. addicted to or characterized by vice; grossly immoral; depraved; profligate: a vicious life. 2. given or readily disposed to evil: a vicious criminal. 3. reprehensible; blameworthy; wrong: a vicious deception. 4. spiteful; malicious: vicious gossip; a vicious attack. 5. unpleasantly severe: a vicious headache. 6. characterized or marred by faults or defects; faulty; unsound: vicious reasoning. 7. savage; ferocious: They all feared his vicious temper. 8. (of an animal) having bad habits or a cruel or fierce disposition: a vicious bull. 9. Archaic.morbid, foul, or noxious.