Synonyms of atrociously

2 Syllables
meanly
3 Syllables
corruptly, brutally, wickedly, fiercely, unkindly, ruthlessly, viciously, brutishly, callously, ferally, heartlessly
4 Syllables
hardheartedly, hatefully, murderously, ferociously, relentlessly, savagely, mercilessly, barbarously, inhumanly, pitilessly
5 Syllables
unrelentingly, inexorably, barbarically, demoniacally, diabolically, inhumanely, remorselessly