Synonyms for Demoniac (same or very similar meaning)
WordNet sense 1 (in a murderous frenzy as if possessed by a demon):
amok, amuck, berserk, demoniacal, possessed
WordNet sense 2 (afflicted with or characteristic of mental derangement):
insane
WordNet sense 3 (troubled emotionally and usually deeply):
agitated
From the ODE community, based on WordNet
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