lunatic

play

adjective lu·na·tic \ ˈlü-nə-ˌtik \

Definition of lunatic

1 dated

a :affected with a severely disordered state of mind :insane

b :designed for the care of mentally ill people

a lunatic asylum

2 :wildly foolish

a lunatic idea

lunatic behavior

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lunatic

noun

See lunatic defined for English-language learners

See lunatic defined for kids

Examples of lunatic in a Sentence

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

Recent Examples of lunatic from the Web

There's an audience out there for every lunatic assertion the president* made.

— charles p. pierce, Esquire, "Maybe Next Time Stick to the Notes," 15 Aug. 2017
One of the cherished myths of conservative history holds that William F. Buckley cast the John Birch Society out of the movement for its lunatic thinking.

— jonathan chait, Daily Intelligencer, "Donald Trump Has Finally Erased the Line Between Conservatism and Conspiracy Theories," 1 Aug. 2017
Ellis died in 2008 of cirrhosis of the liver, but his legacy lives on, regardless of whether or not the acid no-hitter was a flight of fancy or a real, lunatic day.

— jon tayler, SI.com, "Today is the 47th anniversary of Dock Ellis' acid-fueled no-hitter," 12 June 2017
There are parallels between the old Lunatic line and its replacement, said Elias Randiga, the assistant director of the Railway Museum in Nairobi, a stone’s throw from the original Nairobi Station.

— kimiko de freytas-tamura, New York Times, "Kenyans Fear Chinese-Backed Railway Is Another ‘Lunatic Express’," 8 June 2017
Assuming that only the lunatic fringe among Alabama and Ohio State fans has issues with Nick Saban and Urban Meyer, what other fanbases should be totally cool with their coach heading into 2017?

— ralph d. russo, The Denver Post, "These 6 college football fanbases are totally cool with their coach," 7 June 2017
Assuming that only the lunatic fringe among Alabama and Ohio State fans has issues with Nick Saban and Urban Meyer, what other fanbases should be totally cool with their coach heading into 2017?

— ralph d. russo, The Denver Post, "These 6 college football fanbases are totally cool with their coach," 7 June 2017
Assuming that only the lunatic fringe among Alabama and Ohio State fans has issues with Nick Saban and Urban Meyer, what other fanbases should be totally cool with their coach heading into 2017?

— ralph d. russo, The Denver Post, "These 6 college football fanbases are totally cool with their coach," 7 June 2017
Assuming that only the lunatic fringe among Alabama and Ohio State fans has issues with Nick Saban and Urban Meyer, what other fanbases should be totally cool with their coach heading into 2017?

— ralph d. russo, The Seattle Times, "Pick 6: College football fanbases most cool with their coach," 6 June 2017

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

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First Known Use: 14th century

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