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

Had he been found not guilty by reason of insanity, he could have been ordered to undergo mental health treatment. — ABC News, 21 Sep. 2026

There will be recruiting battles and NIL headaches and portal defections and angry message boards and all the other insanity that comes with coaching at a place where fans consider 9-3 an average record rather than an accomplishment. — Mike Bianchi, The Orlando Sentinel, 20 Sep. 2026

The Massachusetts Supreme Judicial Court last month vacated the murder conviction of Brockton mother Latarsha Sanders, ruling jurors were improperly prevented from seeing psychiatric records central to her insanity defense and ordering a new trial. — Greg Wehner, FOXNews.com, 18 Sep. 2026

At a moment when the Lindsay Clancy trial has led to intense cultural debate about the insanity defense, Parker’s tough examination of Barisone’s account of his actions is very timely. — Hannah Jocelyn, New Yorker, 17 Sep. 2026