insane

adjective
in·​sane | \ (ˌ)in-ˈsān \

Definition of insane

1a(1) : exhibiting a severely disordered state of mind : affected with mental illness
(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 mentally ill people 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 … 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

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Other Words from insane

insanely adverb
insaneness \ (ˌ)in-​ˈsān-​nəs \ noun

Synonyms & Antonyms for insane

Synonyms

balmy, barmy [chiefly British], bats, batty, bedlam, bonkers, brainsick, bughouse [slang], certifiable, crackbrained, cracked, crackers, crackpot, cranky [dialect], crazed, crazy, cuckoo, daffy, daft, demented, deranged, fruity [slang], gaga, haywire, kooky (also kookie), loco [slang], loony (also looney), loony tunes (or looney tunes), lunatic, mad, maniacal (also maniac), mental, meshuga (or meshugge), moonstruck, non compos mentis, nuts, nutty, psycho, psychotic, scatty [chiefly British], screwy, unbalanced, unhinged, unsound, wacko (also whacko), wacky (also whacky), wud [chiefly Scottish]

Antonyms

balanced, compos mentis, sane, sound, uncrazy

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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.
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Recent Examples on the Web

Yes, spending nearly $100 on a face scrub is probably insane to a lot of people. Jessica Radloff, Glamour, "This $85 Face Scrub Completely Transformed My Skin," 7 Jan. 2019 Obviously, that won’t apply to today’s or even tomorrow's uses cases, but with Optane storage continuing to move down the train tracks, the day is approaching when even a consumer CPU may need to talk to what seems like an insane amount of memory. Gordon Mah Ung, PCWorld, "Surprise! Intel reveals 10nm Sunny Cove CPU cores that go deeper, wider, and faster," 12 Dec. 2018 Then imagine gutting the house only to find out that open floorplans actually drive you insane. Kate Wagner, Curbed, "To renovate or not to renovate?," 5 Sep. 2018 Interpreting this evidence requires a model, and the models for quark interactions are a bit insane in terms of difficulty, leaving things open to multiple explanations. Chris Lee, Ars Technica, "Quark-gluon plasma reveals viscosity-free properties," 19 Dec. 2018 The plot may be as indecipherable as The Big Sleep but the action is insane in this sixth installment of Mission: Impossible. Todd Mccarthy, The Hollywood Reporter, "'Mission: Impossible — Fallout': Film Review," 12 July 2018 The biggest star is a girl whose face registers insane excitement and curiosity. Sarah Boxer, New York Times, "Weegee the Famous: The Master of Down-and-Dirty Street Photography," 1 June 2018 To be found legally insane, the judge has to agree with the evaluation that Lopez could not tell right from wrong at the time of the slaying on Aug. 23, 2014. Emilie Eaton, San Antonio Express-News, "Man accused of killing Elmendorf police chief is insane, experts say, reducing the likelihood of trial," 2 May 2018 Jesse Daniels was 19 when he was declared incompetent to stand trial and shipped off to a state mental hospital for the criminally insane in Chattahoochee. Lauren Ritchie, OrlandoSentinel.com, "Villages of West Lake 'designed to capture' water, but developer wants millions of gallons more," 29 Apr. 2018

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.

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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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Statistics for insane

Last Updated

21 Jan 2019

Look-up Popularity

Time Traveler for insane

The first known use of insane was in 1575

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More Definitions for insane

insane

adjective
in·​sane | \ in-ˈsān \

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

insane

adjective
in·​sane | \ (ˈ)in-ˈsān \

Medical Definition of insane

dated
1 : exhibiting a severely disordered state of mind
2 : used by, typical of, or intended for insane persons an insane asylum

Other Words from insane

insanely adverb

insane

adjective
in·​sane

Legal Definition of insane

: affected with insanity

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More from Merriam-Webster on insane

Thesaurus: All synonyms and antonyms for insane

Spanish Central: Translation of insane

Nglish: Translation of insane for Spanish Speakers

Britannica English: Translation of insane for Arabic Speakers

Comments on insane

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