lunatic

play
adjective lu·na·tic \ˈlü-nə-ˌtik\

Definition of lunatic

  1. 1 dated a :  affected with a severely disordered state of mind :  insaneb :  designed for the care of mentally ill people a lunatic asylum

  2. 2 :  wildly foolish a lunatic idea lunatic behavior

lunatic

noun

Examples of lunatic in a Sentence

  1. He hatched a lunatic plot to overthrow the government.

  2. another of his lunatic ideas

Recent Examples of lunatic from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lunatic'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology 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


LUNATIC Defined for Kids

1

lunatic

play
adjective lu·na·tic \ˈlü-nə-ˌtik\

Definition of lunatic for Students

  1. :  insane 1


2

lunatic

play
noun lu·na·tic

Definition of lunatic for Students

  1. 1 :  an insane person

  2. 2 :  a person who behaves very foolishly That lunatic went through a red light.


Medical Dictionary

lunatic

noun lu·na·tic

Medical Definition of lunatic

  1. :  an individual marked by a severely disordered state of mind


Law Dictionary

lunatic

noun lu·na·tic \ˈlü-nə-tik\

Legal Definition of lunatic

  1. :  an insane person —used especially formerly

lunatic

adjective


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