insanity

noun
in·​san·​i·​ty | \ in-ˈsa-nə-tē How to pronounce insanity (audio) \
plural insanities

Definition of insanity

1 dated : a severely disordered state of the mind usually occurring as a specific disorder
2 law : unsoundness of mind or lack of the ability to understand that prevents one from having the mental capacity required by law to enter into a particular relationship, status, or transaction or that releases one from criminal or civil responsibility
3a : extreme folly or unreasonableness the insanity of violence His comments were pure insanity.
b : something utterly foolish or unreasonable the insanities of modern life

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Synonyms & Antonyms for insanity

Synonyms

Antonyms

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On the Meaning of Insanity

An oft-quoted bon mot (frequently attributed to Albert Einstein, Benjamin Franklin, or a number of other people who probably never said it) is that insanity may be defined as “doing the same thing over and over and expecting different results.” While the job of lexicographers might be easier if they were allowed to use witty sayings instead of precise definitions, such belletristic labors are not within their purview. The straight facts about insanity are these: it has been in use in English since the late 16th century, for the first two hundred years or so carrying only the literal meaning “the condition of being mentally deranged.” In the 19th century it began to take on a looser sense, “extreme folly or unreasonableness.” In modern usage, insanity may be found in both senses: you may tell your brother that trying to skateboard while holding onto a car is "insanity" (in which case you mean that it is extremely foolish) or encounter the stricter original meaning in such contexts as insanity plea.

Examples of insanity in a Sentence

She was found not guilty by reason of insanity. His friends thought his decision to quit his job was pure insanity. Please, no more violence. It's time to stop this insanity. the insanities of modern life
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Recent Examples on the Web Court records show Wilder was found not guilty of murder by reason of insanity in Tuscaloosa County in the 1980s. al, "Suit filed against Alabama sheriff after mentally ill Black man killed in his home," 29 Apr. 2021 Ramos already has pleaded guilty but not criminally responsible due to insanity. Brian Witte, Star Tribune, "Expert explains mental health report on newspaper gunman," 23 Apr. 2021 In March 2017, a judge dismissed the insanity proceedings, and Watson was transferred to Hamilton County Probate Court. Kevin Grasha, The Enquirer, "Man in murder case who pulled out his eye committed to psychiatric hospital," 6 Apr. 2021 This is legislative insanity that could negatively affect vast portions of the economy. Erik Sherman, Forbes, "How Democrats And Unions Plan To Wipe Out Independent Contractors," 5 Apr. 2021 However, Tuttman’s insanity verdict means Yao faces hospitalization at Bridgewater State Hospital with the legal requirement that his mental status be reviewed annually. BostonGlobe.com, "Jeffrey Yao found not guilty by reason of insanity for fatally stabbing Deane Stryker in Winchester Public Library in 2018," 31 Mar. 2021 Continuity versus insanity aside, pumping new talent into NFL franchises happens every offseason. Ellis L. Williams, cleveland, "What key roles can Anthony Walker and Malik Jackson fill for the Browns defense? -- Film Review," 24 Mar. 2021 Those around the Blowhards, as mentioned, didn’t quite reach that level of extreme insanity. Gordon Monson, The Salt Lake Tribune, "Gordon Monson: One more reminder, BYU and Utah are not enemies, only opponents," 10 Mar. 2021 The production was an instant hit with Bay Area theatergoers, who were eager to welcome back these zany political satirists at a time when there was so much insanity to skewer. Charles Mcnulty, Los Angeles Times, "Theaters hit the one-year anniversary of shutdown. How are artists keeping afloat?," 2 Mar. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'insanity.' 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 insanity

1590, in the meaning defined at sense 1

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Time Traveler for insanity

Time Traveler

The first known use of insanity was in 1590

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Statistics for insanity

Last Updated

13 May 2021

Cite this Entry

“Insanity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insanity. Accessed 14 May. 2021.

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More Definitions for insanity

insanity

noun

English Language Learners Definition of insanity

: severe mental illness : the condition of being insane
: something that is very foolish or unreasonable

insanity

noun
in·​san·​i·​ty | \ in-ˈsa-nə-tē How to pronounce insanity (audio) \

Kids Definition of insanity

: the condition of being abnormal or unhealthy in mind

insanity

noun
in·​san·​i·​ty | \ in-ˈsan-ət-ē How to pronounce insanity (audio) \
plural insanities

Medical Definition of insanity

1 dated : a severely disordered state of the mind usually occurring as a specific disorder
2 law : unsoundness of mind or lack of the ability to understand that prevents one from having the mental capacity required by law to enter into a particular relationship, status, or transaction or that releases one from criminal or civil responsibility

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insanity

noun
in·​san·​i·​ty

Legal Definition of insanity

1 : unsoundness of mind or lack of the ability to understand that prevents one from having the mental capacity required by law to enter into a particular relationship, status, or transaction or that releases one from criminal or civil responsibility: as
a : a disease, defect, or condition of the mind that renders one unable to understand the nature of a criminal act or the fact that it is wrong or to conform one's conduct to the requirements of the law being violated
b : inability to understand and participate in legal proceedings brought against one : incompetence
c : inability to understand the nature and purpose of a punishment (as the death penalty) to which one has been sentenced
d : inability to understand the nature and consequences of one's acts (as making a will) or of events, matters, or proceedings in which one is involved — see also commitment, durham rule, irresistible impulse test, m'naghten test, not guilty by reason of insanity, substantial capacity test — compare capacity, competency, competent, diminished capacity, sanity
2 : the affirmative defense of having acted while insane

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