Synonyms of insanity

insanity

noun

in-ˈsa-nə-tē 

1

as in dementia

a serious mental disorder that prevents one from living a safe and normal life

his incurable insanity requires that he spend the rest of his life in a mental hospital

Synonyms & Similar Words

• dementia
• madness
• hysteria
• schizophrenia
• instability
• paranoia
• mania
• lunacy
• rage
• derangement
• aberration
• delusion
• psychosis
• neurosis
• frenzy
• irrationality
• delirium
• unreasonableness
• obsession
• abnormality
• phobia
• hallucination
• hypomania
• unsoundness
• senile dementia
• monomania
• hallucinosis
• dementedness

Antonyms & Near Antonyms

• sanity
• mind
• rationality
• reasonableness
• lucidity
• saneness
• normality
• soundness
• reasonability
• rationalness

2

as in absurdity

a foolish act or idea

everyone laughed at the latest insanity from the town eccentric

Synonyms & Similar Words

• absurdity
• stupidity
• madness
• idiocy
• craziness
• imbecility
• lunacy
• inanity
• absurdness
• blunder
• foppery
• folly
• foolery
• bêtise
• asininity
• fatuity
• foolishness
• nonsense
• buffoonery
• tomfoolery
• witlessness
• senselessness
• inaneness
• twaddle
• shenanigan(s)
• monkeyshine(s)
• drivel
• flub
• bungle
• goof
• howler
• humbug

Antonyms & Near Antonyms

• wisdom
• discretion
• prudence
• sagacity
• inspiration
• forethought
• brainstorm

3

as in madness

lack of good sense or judgment

had the insanity to think that taking over a government building in protest of our foreign policy was a good idea

Synonyms & Similar Words

• madness
• simplicity
• craziness
• absurdity
• wackiness
• foolishness
• lunacy
• zaniness
• unwisdom
• imbecility
• nuttiness
• daftness
• inanity
• fatuousness
• silliness
• preposterousness
• dottiness
• witlessness
• stupidness
• folly
• brainlessness
• senselessness
• nonsensicalness
• stupidity
• asininity
• idiocy
• balminess
• fatuity
• irrationality
• feeblemindedness
• dullness
• dippiness
• dumbness
• slowness
• obtuseness
• mindlessness
• unreasonableness
• simpleness
• ridiculousness
• simplemindedness
• dopiness
• denseness
• oafishness
• doltishness
• kookiness
• weirdness
• fallacy
• ludicrousness
• gormlessness
• vacuity
• dim-wittedness
• laughableness

Antonyms & Near Antonyms

• sanity
• wisdom
• soundness
• prudence
• sagacity
• rationality
• validity
• reasonableness
• sapience
• sensibleness
• reasonability
• logicality
• perception
• insight
• sagaciousness
• sageness
• discernment
• logicalness
• rationalness
• percipience

Example Sentences

Recent Examples of insanity

Counsel was enraged that his gambit was foiled by one jury holdout on the insanity argument. — Voice Of The People, New York Daily News, 2 Oct. 2026

Prosecutors questioned the schizophrenia diagnosis and pointed out that suffering from mental illness is not the same as meeting the legal standard of insanity. — Clara Harter, Los Angeles Times, 1 Oct. 2026

Staging a movie of broad scolding maximalism isn’t the same thing as staging a movie of debonair satirical insanity. — Owen Gleiberman, Variety, 29 Sep. 2026

Since the trial ended, various statements given to the media from jurors have indicated that the jury was hung 11-1 in favor of not guilty by reason of insanity. — Kristina Rex, CBS News, 28 Sep. 2026