Definition of (as) mad as a March hare in English:

(as) mad as a March hare

phrase

informal
  • (of a person) completely mad or irrational; crazy.

    • ‘You're mad as a March hare madam, but your questions are funny.’
    • ‘Phil's as mad as a March hare by the way: when he kicks off he kicks off.’
    • ‘‘One would have to be madder than a March hare to fail to see the need to act,’ said the Senator.’
    • ‘"You're mad as a March hare," she said. "Let me by!"’
    severely mentally ill, mentally ill, insane, mad, certifiable, deranged, demented, of unsound mind, out of one's mind, not in one's right mind, not together, crazed, maniac, maniacal, lunatic, unbalanced, unhinged, unstable, disturbed, distracted, stark mad, manic, frenzied, raving, distraught, frantic, hysterical, delirious, mad as a hatter, mad as a march hare
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