Synonyms of ferocious

1 Syllable
cruel, fell, grim, wild
2 Syllables
crueler, brutish, ruthless, fiercest, angrier, cruelest, brutal, wolfish, wildest, fierce, grimmer, vicious, fiercer, frightful, feller, cutthroat, angriest, feral, hang-tough, grimmest, wilder, angry, jousting, fighting
3 Syllables
ruffianly, inhuman, sanguineous, slaughterous, pitiless, murderous, truculent, tigerish, rapacious, lupine, ravenous, voracious, merciless, savage, ravening, coldblooded, barbarous, untamed, ferine, vehement, tameless, relentless, bloodthirsty, creophagous, hard-shelled
4 Syllables
implacable, predatory, unmerciful, sanguinary, unrestrained, inhumane
5 Syllables
disputative
6 Syllables
undomesticated