insane
adjective
in·sane (ˌ)in-ˈsān 
1
a(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
Hunter S. ThompsonMore than 22,000 athletes descend on Philadelphia's Franklin Field to chug insane amounts of Gatorade … Chris Ballard
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
Tom Wheatley With his rough-edged baritone and ear for insane hooks, [reggae singer] Baby Cham always sounds wicked. Rob Kenner
Rob Kenner insaneness
(ˌ)in-ˈsān-nəs
noun 
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
- kookie
- loco [slang]
- loony
- looney
- loony tunes
- looney tunes
- lunatic
- mad
- maniacal
- maniac
- mental
- meshuga
- meshugge
- meshugah
- meshuggah
- moonstruck
- non compos mentis
- nuts
- nutty
- psycho
- psychotic
- scatty [chiefly British]
- screwy
- unbalanced
- unhinged
- unsound
- wacko
- whacko
- wacky
- whacky
- wud [chiefly Scottish]
See all Synonyms & Antonyms 
Example Sentences
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 So to fulfill that fantasy of doing these bands was insane. Dewayne Bevil, Orlando Sentinel, 14 Sep. 2022 Their performance has got to be over 11 million views, which is insane. Paul Grein, Billboard, 31 Aug. 2022 My final excessive add-on was the Burmester surround sound system, which costs an insane $4500. Car and Driver, 3 Sep. 2022 The Cold War has ended, the arms race has stopped, as has the insane militarization which mutilated our economy, public psyche and morals. ABC News, 30 Aug. 2022 On the plus side, Carell's portrayal is refreshingly real in terms of the character's fears in this insane situation, challenging the familiar practice of transforming an ordinary person into a superhero under perilous circumstances. Brian Lowry, CNN, 30 Aug. 2022 They’re fully formed in their demeanors and their behaviors and their insane ways sometimes. Adrienne Gaffney, ELLE, 23 Aug. 2022 As with most of Webb’s insane discoveries, these images of auroras on Jupiter were captured using infrared light. Joshua Hawkins, BGR, 23 Aug. 2022 Moon also demonstrates how the sci-fi genre doesn't need insane CGI budgets to be great. Josh St. Clair, Men's Health, 18 Aug. 2022 See More
Dewayne Bevil, Orlando Sentinel, 14 Sep. 2022 Their performance has got to be over 11 million views, which is insane. Paul Grein, Billboard, 31 Aug. 2022 My final excessive add-on was the Burmester surround sound system, which costs an insane $4500. Car and Driver, 3 Sep. 2022 The Cold War has ended, the arms race has stopped, as has the insane militarization which mutilated our economy, public psyche and morals. ABC News, 30 Aug. 2022 On the plus side, Carell's portrayal is refreshingly real in terms of the character's fears in this insane situation, challenging the familiar practice of transforming an ordinary person into a superhero under perilous circumstances. Brian Lowry, CNN, 30 Aug. 2022 They’re fully formed in their demeanors and their behaviors and their insane ways sometimes. Adrienne Gaffney, ELLE, 23 Aug. 2022 As with most of Webb’s insane discoveries, these images of auroras on Jupiter were captured using infrared light. Joshua Hawkins, BGR, 23 Aug. 2022 Moon also demonstrates how the sci-fi genre doesn't need insane CGI budgets to be great. Josh St. Clair, Men's Health, 18 Aug. 2022 See More Word History
Etymology
Latin insanus, from in- + sanus sane
First Known Use
1575, in the meaning defined at sense 1a(1)
Phrases Containing insane
Kids Definition
insane
adjective
in·sane in-ˈsān
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
insane
adjective
in·sane (ˈ)in-ˈsān
1
dated : exhibiting a severely disordered state of mind
2
law : affected with insanity (see insanity sense 2)
Legal Definition
insane
adjective
in·sane
: affected with insanity
insane
adjective
1
as in psychotic
having or showing a very abnormal or sick state of mind only an insane person would intentionally jump off a skyscraper Synonyms & Similar Words
Relevance
- psychotic
- lunatic
- mad
- nuts
- crazy
- maniac
- maniacal
- gaga
- mental
- paranoid
- crazed
- psycho
- bonkers
- deranged
- unhinged
- disturbed
- demented
- irrational
- strange
- wacko
- loony
- nutty
- batty
- daft
- screwy
- unbalanced
- wacky
- cuckoo
- bedlam
- haywire
- certifiable
- eccentric
- cracked
- looney
- ballistic
- paranoidal
- whacky
- unreasonable
- barmy
- kooky
- around the bend
- odd
- foolish
- obsessed
- daffy
- bughouse
- whacko
- crackpot
- depressed
- bats
- brainsick
- loco
- moonstruck
- crackers
- unsound
- scatty
- kookie
- crackbrained
- meshuga
- loony tunes
- out to lunch
- frantic
- distraught
- meshuggah
- hysterical
- off
- fruity
- looney tunes
- schizophrenic
- delusional
- distracted
- delirious
- cranky
- meshugah
- wud
- fey
- meshugge
- neurotic
- balmy
- loopy
- sociopathic
- schizoid
- out of one's mind
- off one's rocker
- delusionary
- paranoiac
- touched
- off one's gourd
- non compos mentis
- off one's head
- hysteric
- oddball
- queer
- disordered
- out of one's head
- aberrant
- dotty
- berserk
- nuclear
- paranoic
- raving
- bananas
- witless
- obsessive-compulsive
- tetched
- senseless
- pixilated
- monomaniacal
- amok
- frenzied
- ape
- teched
- potty
- monomaniac
- fixated
- pixillated
- amuck
- wigged-out
Antonyms & Near Antonyms
- sane
- reasonable
- sound
- balanced
- rational
- clear
- normal
- compos mentis
- wise
- uncrazy
- sensible
- lucid
- judicious
- healthy
- well-adjusted
- unneurotic
2
as in absurd
conceived or made without regard for reason or reality a completely insane plan to build an opera house in the middle of nowhere Synonyms & Similar Words
- absurd
- bizarre
- foolish
- unreal
- crazy
- ridiculous
- fantastic
- strange
- fantastical
- incredible
- nonsensical
- wild
- preposterous
- fanciful
- weird
- grotesque
- curious
- unbelievable
- peculiar
- odd
- funny
- inconceivable
- unimaginable
- unthinkable
- eccentric
- implausible
- off the wall
- ludicrous
- extravagant
- outlandish
- wacky
- screwy
- surreal
- laughable
- outré
- nightmarish
- quirky
- bizarro
- whacky
- kooky
- kinky
- farcical
- quaint
- queer
- dreamlike
- kookie
- way-out
- far-out
- queerish
- Alice-in-Wonderland
- out-of-the-way
- Kafkaesque
Antonyms & Near Antonyms
- reasonable
- realistic
3
as in crazy
showing or marked by a lack of good sense or judgment an insane plan to blow all of their savings on lottery tickets Synonyms & Similar Words
- crazy
- stupid
- absurd
- mad
- silly
- foolish
- lunatic
- idiotic
- irrational
- ridiculous
- fool
- dumb
- unreasonable
- loony
- zany
- nonsensical
- wacky
- nutty
- asinine
- daft
- simple
- preposterous
- unwise
- weak
- kooky
- idiotical
- looney
- senseless
- fatuous
- slow
- whacky
- screwball
- inept
- daffy
- crackpot
- witless
- cuckoo
- dotty
- unreasoning
- simpleminded
- brainless
- dippy
- harebrained
- jerky
- moronic
- tomfool
- sappy
- illogical
- ludicrous
- imbecile
- kookie
- lunkheaded
- balmy
- cockeyed
- weak-minded
- half-baked
- bubbleheaded
- clueless
- featherheaded
- thoughtless
- obtuse
- feebleminded
- unreasoned
- out to lunch
- half-witted
- laughable
- unintelligent
- dopey
- dense
- mindless
- lamebrain
- invalid
- dull
- thickheaded
- vacuous
- doltish
- farcical
- dorky
- dunderheaded
- pinheaded
- dim
- fallacious
- opaque
- imbecilic
- thick
- unsound
- oafish
- airheaded
- nonrational
- softheaded
- soft
- surd
- gormless
- knuckleheaded
- brain-dead
- lamebrained
- clownish
- chuckleheaded
- dim-witted
- empty-headed
- buffoonish
- notional
- boobish
- chowderheaded
- birdbrained
- dopy
- slow-witted
- unconsidered
- ill-advised
Antonyms & Near Antonyms
- sane
- wise
- sensible
- sound
- prudent
- reasonable
- judicious
- sagacious
- intelligent
- clever
- smart
- logical
- rational
- valid
- bright
- sage
- sapient
- brainy
- well-advised
4
as in excessive
going beyond a normal or acceptable limit in degree or amount wanted an insane amount of money to paint our house Synonyms & Similar Words
- excessive
- extreme
- extravagant
- steep
- endless
- infinite
- exorbitant
- lavish
- intolerable
- unconscionable
- inordinate
- unbearable
- undue
- baroque
- fancy
- immoderate
- devilish
- unmerciful
- plethoric
- inappropriate
- overextravagant
- overdue
- towering
- unjustifiable
- overweening
- limitless
- stiff
- over the top
- a bit much
- overmuch
- improper
- unwarranted
- boundless
- immeasurable
- unseemly
- unrestrained
- thick
Antonyms & Near Antonyms
- reasonable
- moderate
- inadequate
- modest
- insufficient
- deficient
- minimal
- minimum
- middling
- temperate
- undertreated
- undertreating
- undertreats
- undertrick
- undertricks
- undertrimmer
- undertrump
- undertrumped
- undertrumping
- undertrumps
- underturner
- underused
- underuses
- underusing
- underutilisation
- underutilisations
- underutilise
- underutilised
- underutilises
- underutilising
- underutilization
- underutilizations
- underutilize
- underutilized
- underutilizes