Synonyms of vicious

1 Syllable

foul, lewd, cruel, bad, base, vile, wild, fouls

2 Syllables

miscreant, nighthawk, crueler, heinous, impious, monstrous, slummier, sordid, bitchy, wilder, cattier, furious, cattish, fiendish, spleenful, fiercest, sinful, brutal, evil, lousy, rotten, putrid, lowbrow, fiercer, catty, cutthroat, foulest, maligns, fouled, ruthless, septic, violent, viler, slumer, wicked, bitchier, hellish, cruelest, toucher, vilest, wildest, unfair, lousier, feller, faulty, worthless, slummy, fouler, ogreish, malign, dickens, scurvy

3 Syllables

dog-eat-dog, barbarian, mischievous, malicious, flagitious, toxicant, teratoid, venomous, ireful, rascally, spiteful, pestilent, atrocious, ornery, vehement, licentious, satanic, maligning, villainous, impure, unsporting, ill-famed, degraded, sadistic, coldblooded, criminal, barbarians, depraved, viperous, malefic, infamous, imperfect, liverish, dangerous, hateful, miscreated, hard-shelled, ferocious, ruffianly, inhuman, immoral, perverted, diabolic, abhorrent, debased, viperish, tigerish, poisonous, savage, barbarous, untamed, hardnosed, flatitious, indecent, nefarious, perverse

4 Syllables

ill-behaved, libidinous, ill-tempered, dissolute, iniquitous, demonical, abandoned, inhumane, unprincipled, profligate, maleficent, mephitical, indictable, bad-natured, despiteful, satanical, reprobate, diabolical, malevolent

5 Syllables

disreputable, reprehensible, contaminated, bottom-of-barrel, degenerate, degenerated, demoralized

6 Syllables

insubordinate, undomesticated