mad as a hatter
Definition of mad as a hatter
informal + old-fashioned
: severely mentally ill : crazy He's a nice fellow, but mad as a hatter.
Word by Word Definitions
: completely unrestrained by reason and judgment : unable to think in a clear or sensible way
: incapable of being explained or accounted for
: carried away by intense anger : very angry : furious
: a fit or mood of bad temper
: anger, fury
: one that makes, sells, or cleans and repairs hats
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