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. noun
    an insane person
    synonyms: lunatic, madman
    see moresee less
    show 4 types...
    hide 4 types...
    crazy, looney, loony, nutcase, weirdo
    someone deranged and possibly dangerous
    an archaic term for a lunatic
    a person with a mania for setting things on fire
    a woman lunatic
    type of:
    diseased person, sick person, sufferer
    a person suffering from an illness
  2. noun
    a person who has an obsession with or excessive enthusiasm for something
    see moresee less
    type of:
    enthusiast, fancier
    a person having a strong liking for something
  3. adjective
    wildly disordered
    synonyms: maniacal
    afflicted with or characteristic of mental derangement
Word Family

Test prep from the experts

Boost your test score with programs developed by’s experts.

  • Proven methods: Learn faster, remember longer with our scientific approach.
  • Personalized plan: We customize your experience to maximize your learning.
  • Strategic studying: Focus on the words that are most crucial for success.


  • Number of words: 500+
  • Duration: 8 weeks or less
  • Time: 1 hour / week


  • Number of words: 500+
  • Duration: 10 weeks or less
  • Time: 1 hour / week


  • Number of words: 700+
  • Duration: 10 weeks
  • Time: 1 hour / week