Definition of insane
1a (1) : exhibiting a severely disordered state of mind : affected with mental illness (2) law : affected with insanity (see insanity 2) criminally insaneb : 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 : extreme 1
insanenessplay \(ˌ)in-ˈsān-nəs\ noun
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 of insane from the Web
An insane surgeon's obsession with an actress leads him to replace her husband's hands with the hands of a knife murderer which still have the urge to throw knives.
That sub-nine minute 1.5 miles, after a rapid 500 yard swim, 100 push ups, 100 more curls and 20 pull ups is insane.
But why do its tellers seem to think that the American night has no stars, nothing but bats and owls and the insane moon?
Looking back, the decision to get in his car seems completely insane.
Best Buy’s sticker price for this drive is $100, which is an absolutely insane price any day of the year.
Christopher Muma’s single set, a dingy room that could be a docklands warehouse, has to serve as a barber’s parlor, a pie shop, an insane asylum and other Victorian London locales.
CLEVELAND—Game 4 of the NBA Finals was insane, inexplicable and maybe even inconsequential.
Based on the buzz and reviews for Jordan Peele’s unsettling horror film, my anticipation was driving me insane.
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.
Origin and Etymology of insane
Latin insanus, from in- + sanus sane
First Known Use: circa 1550See Words from the same year
INSANE Defined for Kids
Definition of insane for Students
1 : not normal or healthy in mind
2 : used by or for people who are insane an insane asylum
3 : very foolish or unreasonable
Medical Definition of insane
1dated : exhibiting a severely disordered state of mind
2: used by, typical of, or intended for insane persons an insane asylum
Legal Definition of insane
: affected with insanity
Seen and Heard
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