Vicious1. (a.) Characterized by vice or defects; defective; faulty; imperfect.
2. (a.) Addicted to vice; corrupt in principles or conduct; depraved; wicked; as, vicious children; vicious examples; vicious conduct.
3. (a.) Wanting purity; foul; bad; noxious; as, vicious air, water, etc.
4. (a.) Not correct or pure; corrupt; as, vicious language; vicious idioms.
5. (a.) Not well tamed or broken; given to bad tricks; unruly; refractory; as, a vicious horse.
6. (a.) Bitter; spiteful; malignant.
Thesaurus Entries
Draconian, Tartarean, abominable, acrimonious, amoral, animal, anthropophagous, arrant, atrocious, bad, baleful, baneful, barbaric, barbarous, base, beastly, bestial, bitchy, bitter, black, blamable, blameworthy, bloodthirsty, bloody, bloody-minded, brutal, brutalized, brute, brutish, cannibalistic, concentrated, contaminated, corroding, corrosive, corrupt, corrupting, corruptive, counterproductive, criminal, cruel, cruel-hearted, damaging, damnable, dark, deadly, defamatory, degenerate, degraded, degrading, deleterious, demoniac, demoniacal, depraved, desperate, despiteful, detrimental, devilish, diabolic, diabolical, disadvantageous, disgraceful, disserviceable, distressing, evil, execrable, exquisite, faulty, fearful, fell, feral, ferine, ferocious, fiendish, fiendlike, fierce, flagitious, flagrant, foul, furious, harmful, hateful, heinous, hellish, hurtful, ill, immoral, improper, inaccurate, inauspicious, inexpedient, infamous, inferior, infernal, inhuman, inhumane, iniquitous, injurious, invalid, kill-crazy, knavish, lethal, low, malefic, malevolent, malicious, malign, malignant, mean, merciless, mischievous, miscreant, monstrous, murderous, nasty, naughty, nefarious, noisome, noncivilized, nonmoral, noxious, obnoxious, odious, ominous, opprobrious, peccant, pernicious, perverse, perverted, pitiless, poisonous, poor, prejudicial, profligate, putrid, rancorous, rank, ravening, reprehensible, reprobate, rotten, ruthless, sadistic, sanguinary, sanguineous, satanic, savage, scandalous, scatheful, septic, severe, shameful, shameless, sharkish, sinful, sinister, slanderous, slavering, spiteful, steeped in vice, subhuman, tameless, terrible, toxic, truculent, unchristian, uncivilized, unfavorable, unforgivable, ungentle, unhealthy, unhuman, unkind, unmoral, unpardonable, unpleasant, unprincipled, unskillful, unsound, unspeakable, untamed, untoward, unworthy, vehement, venal, venenate, veneniferous, venenous, venomous, vice-laden, vice-prone, vile, villainous, vindictive, violent, virulent, wicked, wild, wolfish, wrong