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Definitions

insane

[in-seyn] / ɪnˈseɪn /
ADJECTIVE
mad
Synonyms
STRONGEST
crazy delirious demented deranged frantic frenzied kooky nutty
WEAK
aberrant bananas batty crazed cuckoo daft frenetic loony lunatic non compos mentis of unsound mind off one's rocker out of one's mind raving unbalanced unhinged unsound unstable
Antonyms
STRONGEST
balanced calm collected rational reasonable sane sensible wise
WEAK
OK sound unenthusiastic

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.

Most people who do this have this insane sense of “Come on in,” and I don’t see the value of that at all.

From Los Angeles Times • Apr. 23, 2026

Grieving is also time to get angry and justified in your own insane behavior.

From Slate • Apr. 23, 2026

She smacked her back on a rock and had "insane" pressure across her back that was spreading into her stomach.

From BBC • Apr. 18, 2026

Shipping costs are up, too, Ferreri said, describing "insane" prices for the delivery of essential farm equipment.

From Barron's • Apr. 11, 2026

I’d been riding the school bus with Cletus for a year, since his family moved up from Raleigh County, and I had decided he was insane.

From "Missing May" by Cynthia Rylant

Vocabulary lists containing insane

salu, san (health)

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