in·​sane | \ (ˌ)in-ˈsān How to pronounce insane (audio) \

Definition of insane

1a(1) : exhibiting a severely disordered state of mind
(2) law : affected with insanity (see insanity sense 2) criminally insane
b : unable to think in a clear or sensible way : crazy insane with jealousy not used technically
2 : used by, typical of, or intended for people having a severely disordered state of mind an insane asylum
3 : absurd an insane scheme for making money
4 informal : outrageously high or extreme making insane amounts of money The monster truck pursued him at insane speeds …— Hunter S. Thompson More than 22,000 athletes descend on Philadelphia's Franklin Field to chug insane amounts of Gatorade …— Chris Ballard also : exceptionally good or impressive Minnesota … has blazed out to an insane start, taking an early lead in the Northwest Division. — Tom Wheatley With his rough-edged baritone and ear for insane hooks, [reggae singer] Baby Cham always sounds wicked. — Rob Kenner

Other Words from insane

insaneness \ (ˌ)in-​ˈsān-​nəs How to pronounce insane (audio) \ noun

Synonyms & Antonyms for insane



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Examples of insane in a Sentence

The murderer was found to be criminally insane. She was insane with jealousy. He had an insane look in his eyes. She likes to drive at insane speeds. He had this insane idea that he could get rich by selling old computers.
Recent Examples on the Web And for those countries to be in conflict like this is insane to me. Jevon Phillips, Los Angeles Times, 18 May 2022 The former partner and mentor of main character special agent Dale Cooper (Kyle MacLachlan), Earle went insane and murdered his wife. Wilson Chapman, Variety, 7 May 2022 The Ohio race was particularly insane: a half-dozen candidates reportedly spent at least sixty-six million dollars, and many of them tried to ape Trump’s style and seek his endorsement. The New Yorker, 4 May 2022 Ironically, as a matter of nuclear warfighting theory, the Russian threat isn’t totally insane. Michael Peck, Forbes, 3 May 2022 After her second husband went insane, founder Fones married her third husband without an official divorce. The Editors, Robb Report, 10 Apr. 2022 Madness clearly abounded in the high command, but three countries going insane in the same way at the same time isn’t exactly a satisfying explanation. Daniel Immerwahr, The Atlantic, 4 Apr. 2022 Almost exclusively eBay, which sounds insane but is brilliant. Liana Satenstein, Vogue, 4 Mar. 2022 Their domination can be explained by a simple ideology that sounds more or less insane to the rest of the world. Ben Cohen, WSJ, 7 Feb. 2022 See More

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

First Known Use of insane

1575, in the meaning defined at sense 1a(1)

History and Etymology for insane

Latin insanus, from in- + sanus sane

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Dictionary Entries Near insane

ins and outs


insane asylum

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Statistics for insane

Last Updated

23 May 2022

Cite this Entry

“Insane.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for insane


in·​sane | \ in-ˈsān How to pronounce insane (audio) \

Kids Definition of insane

1 : not normal or healthy in mind
2 : used by or for people who are insane an insane asylum
3 : very foolish or unreasonable

Other Words from insane

insanely adverb


in·​sane | \ (ˈ)in-ˈsān How to pronounce insane (audio) \

Medical Definition of insane

1 dated : exhibiting a severely disordered state of mind
2 law : affected with insanity (see insanity sense 2)

Other Words from insane

insanely adverb



Legal Definition of insane

: affected with insanity

More from Merriam-Webster on insane

Nglish: Translation of insane for Spanish Speakers

Britannica English: Translation of insane for Arabic Speakers


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