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insane

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adjective British English pronunciation: insane /ɪnˈseɪn/
  1. 1
    informal very stupid or crazy, especially in a way that is likely to cause serious problems, harm, or injury

    It's an insane situation that I can't see any way out of.

    be insane to do something:

    You'd be totally insane to see him again.

  2. 2
    old-fashioned suffering from very severe mental illness so that you cannot be considered legally responsible for your actions
    certify/declare someone insane:

    He was certified insane in 1998.

derived word

insanely

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