lunatic

adjective

lu·​na·​tic ˈlü-nə-ˌtik How to pronounce lunatic (audio)
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
lunatic noun

Example Sentences

He hatched a lunatic plot to overthrow the government. another of his lunatic ideas
Recent Examples on the Web In an idyllic cabin in the woods, a deaf author named Maddie is trying out new recipes, avoiding her ex-boyfriend's phone calls, and trying to combat writer's block, all while a crazed lunatic waits to strike. K. Thor Jensen, PCMAG, 20 Oct. 2022 One small exchange, one ship sunk for another, would become a lunatic conflagration. Ian Mcewan, The New Yorker, 1 Aug. 2022 There’s no malice involved in lunatic-appeasement, however. Erik Wemple, Washington Post, 19 July 2022 Meanwhile, mom Linda (John Roberts) cheerleads with lunatic optimism. Amy Nicholson, Variety, 23 May 2022 Having long since given up on reigning in the enormous lunatic wing of their party, Republican leaders had, particularly after the rise of Donald Trump, began actively catering to it. Alex Shephard, The New Republic, 20 Apr. 2022 The point of such a response would be to portray the Democrats as the reasonable party upholding moderation and decency in the face of a lunatic assault on the rights and freedoms of the female half of the population. Damon Linker, The Week, 1 Apr. 2022 After the trial, Tyler was sent to lunatic asylum [sic] receiving psychological treatment. Patrick Frater, Variety, 7 Feb. 2022 After the trial, Tyler was sent to lunatic asylum [sic] receiving psychological treatment. Patrick Frater, Variety, 7 Feb. 2022 See More

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.

Word History

Etymology

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, in the meaning defined at sense 1a

Time Traveler
The first known use of lunatic was in the 14th century

Dictionary Entries Near lunatic

Cite this Entry

“Lunatic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lunatic. Accessed 2 Dec. 2022.

Kids Definition

lunatic 1 of 2

adjective

lu·​na·​tic
ˈlü-nə-ˌtik
1
a
: insane sense 1
used chiefly in the past
b
: designed for insane persons
lunatic asylum
used chiefly in the past
2
: wildly foolish
a lunatic idea

lunatic

2 of 2

noun

: an insane person
used chiefly in the past

Medical Definition

lunatic

noun

lu·​na·​tic ˈlü-nə-ˌtik How to pronounce lunatic (audio)
dated, now offensive : an individual marked by a severely disordered state of mind

Legal Definition

lunatic

noun

lu·​na·​tic
ˈlü-nə-tik
: an insane person
used especially formerly
lunatic adjective

More from Merriam-Webster on lunatic

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