be as mad as a March hare

be as mad as a March hare

  (old-fashioned)
to be crazy This woman was dancing in the road and singing very loudly - I thought she was mad as a March hare.
See also: hare, mad, march
References in periodicals archive ?
Everyone is entitled to be as mad as a March Hare, and I am delighted I went through my phases at 14-16 before I started my life.