Definition of insane
- insane with jealousy
- an insane asylum
- an insane scheme for making money
The murderer was found to be criminally insane.
She was insane with jealousy.
He had an insane look in his eyes.
She likes to drive at insane speeds.
He had this insane idea that he could get rich by selling old computers.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'insane.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: circa 1550See Words from the same year
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