adjective lu·na·tic \ˈlü-nə-ˌtik\

Definition of LUNATIC

a :  affected with lunacy :  insane
b :  designed for the care of insane persons <lunatic asylum>
:  wildly foolish <a lunatic idea>
lunatic noun

Examples of LUNATIC

  1. He hatched a lunatic plot to overthrow the government.
  2. another of his lunatic ideas

Origin of LUNATIC

Middle English lunatik, from Anglo-French or Late Latin; Anglo-French lunatic, from Late Latin lunaticus, from Latin luna; from the belief that lunacy fluctuated with the phases of the moon
First Known Use: 14th century

Other Psychology Terms

fetish, hypochondria, intelligence, mania, narcissism, neurosis, pathological, psychosis, schadenfreude, subliminal


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