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Definitions

insanity

[in-san-i-tee] / ɪnˈsæn ɪ ti /
NOUN
mental illness; foolishness
Synonyms
STRONGEST
absurdity alienation craziness folly frenzy hysteria irresponsibility lunacy madness mental disorder
STRONG
aberration delirium delusion derangement distraction hallucination irrationality mania neurosis phobia psychopathy psychosis senselessness unbalance
WEAK
preposterousness unreasonableness witlessness
Antonyms
STRONG
balance certainty fact reality truth
WEAK
sanity soundness wellness

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Only a jury can return a verdict of "not guilty by reason of insanity".

From BBC • Mar. 20, 2026

That entire pseudo-event was one one of those blink-and-you-miss-it moments that get drowned out in the endless baying insanity of our collective reality.

From Salon • Feb. 28, 2026

That flying blob of insanity isn’t for everyone.

From The Wall Street Journal • Feb. 16, 2026

“I don’t get where all this insanity is coming from.”

From MarketWatch • Feb. 3, 2026

And then I realize the full extent of the insanity.

From "Will Grayson, Will Grayson" by John Green and David Levithan

Vocabulary lists containing insanity

Adrift

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salu, san (health)

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