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lunatic

American  
[loo-nuh-tik] / ˈlu nə tɪk /

noun

  1. (no longer in technical use; now considered offensive) an insane person.

  2. a person whose actions and manner are marked by extreme eccentricity or recklessness.

  3. a person legally declared to be of unsound mind and who therefore is not held capable or responsible before the law: a former legal term.


adjective

  1. (no longer in technical use; now considered offensive) insane.

  2. characteristic or suggestive of lunacy; wildly or recklessly foolish.

  3. Older Use. designated for or used by the insane.

    a lunatic asylum.

  4. gaily or lightheartedly mad, frivolous, eccentric, etc..

    She has a lunatic charm that is quite engaging.

lunatic British  
/ ˈluːnətɪk /

adjective

  1. an archaic word for insane

  2. foolish; eccentric; crazy

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. a person who is insane

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • half-lunatic adjective
  • lunatically adverb

Etymology

Origin of lunatic

1250–1300; Middle English lunatik, from Old French lunatique, from Late Latin lūnāticus “moonstruck.” See Luna, -tic ( def. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

He got back everything he’s wanted and then a lunatic billionaire is telling you that 100 miles away under the Denver Airport there’s this thing that sounds crazy.

From Los Angeles Times

He looked at me like I was a lunatic, but he heard me, so perhaps I planted a seed.

From The Wall Street Journal

As Raftery writes, television and films had, at the time, generated the notion that serial killers were “unhinged lunatics,” but the agents discovered a different side.

From Los Angeles Times

That is a deliberate choice, says Tracy, because Teddy is not -- or at least not just -- a lunatic.

From Barron's

That Tomás, who has already survived the Great Hunger as well as a cruel workhouse, isn’t already a lunatic is perhaps less fantastical than the plot itself at times.

From Los Angeles Times