maniac

A maniac is a crazy person. Screaming like a maniac is never a good way to get your point across.

Long ago, the word maniac was an official psychiatric term that meant "a patient suffering from mania," or manic disorder, involving a euphoric mood and extreme energy. Maniac isn't used in a clinical way anymore, but only informally to mean "lunatic." You might describe yourself running around the house like a maniac looking for your car keys, or dismiss your sports-obsessed brother as "a football maniac." The Greek root is mania, or "madness."

Definitions of maniac
1

n an insane person

Synonyms:
lunatic, madman
Types:
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hide 4 types...
crazy, looney, loony, nutcase, weirdo
someone deranged and possibly dangerous
bedlamite
an archaic term for a lunatic
pyromaniac
a person with a mania for setting things on fire
madwoman
a woman lunatic
Type of:
diseased person, sick person, sufferer
a person suffering from an illness

n a person who has an obsession with or excessive enthusiasm for something

Type of:
enthusiast, fancier
a person having a strong liking for something

adj wildly disordered

Synonyms:
maniacal
insane
afflicted with or characteristic of mental derangement

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