adjective

insane

insane, mad, crazy, foolish

The man was declared legally insane.

The man was declared legally insane.

That's an insane idea!

That's an insane idea!

The traffic was insane this morning.

The traffic was insane this morning.

to be insane (sb./sth.) is insane The man was declared legally insane.

an insane ((noun)) a foolish or outrageous (idea, plan, etc.) That's an insane idea!

Synonyms: crazy, mad, lunatic; Antonyms: sane, rational, sensible

From the prefix 'in-' (not) + Latin 'sanus' (healthy, sane). Literally means 'not sane'.

Think 'in-sane' -> 'not sane'. Picture someone doing something completely illogical.

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