Synonyms for Madman:

adj.

lunatic (adjective)
fool, bedlamite, raver, insane man, screwball, stir-nut, cuckoo, crazyman, psychiatric patient, psycho, oddball, one who is mentally ill, deranged person, looney.

n.

cabbage, backward, cripple, humpback, dwarf, imbecile, hunchback. headcase, space cadet, nutjob, oddity, madwoman, eccentric. lunatic (noun)
fiend, deranged person, screwball, psychotic, nut, kook, psychopath, raver, looney, oddball, crazy, crackpot, cuckoo, psycho, crazyman, lunatic, maniac, insane man, neurotic, crank, psychiatric patient, bedlamite.

Other synonyms:

humpback, headcase, hunchback, screwball, cabbage, space cadet, oddball, nutjob, imbecile. oddity, psycho, madwoman. dwarf, eccentric, cripple. backward. Other relevant words:
imbecile, nutjob, oddball, humpback, eccentric, backward, screwball, psycho, psychiatric patient, raver, hunchback, fool, deranged person, headcase, bedlamite, dwarf, crazyman, looney, cripple, cabbage, cuckoo, oddity, insane man, madwoman.

Usage examples for madman

  1. Still Habrunt dared not make a reply to this madman – Si'Wren of the Patriarchs by Roland Cheney
  2. But his eyes were not those of a madman – "The Pomp of Yesterday" by Joseph Hocking
  3. He broke, like a madman into the heart of the crowd, sending it flying. – The Prelude to Adventure by Hugh Walpole