Mad as a hatter
Suggest a CorrectionMeaning
Extremely irrational or eccentric. The expression is old-fashioned, and describing a real person's mental health this way may be insensitive.
Origin
Mad as a hatter is in print by 1827, decades before Lewis Carroll's Alice's Adventures in Wonderland, so Carroll did not coin it. Hatters genuinely suffered neurological and psychiatric effects from mercury compounds used in felt making, and that occupational disease makes a connection plausible. However, the direct link between the disease and the creation of this comic simile is circumstantial and disputed by etymologists; other slang and dialect explanations have also been proposed. The safest account records the early date and the real mercury hazard without claiming that the latter is proved to be the phrase's source.
Research Sources
Variants
- As mad as a hatter
Usage Examples
- The narrator calls the inventor mad as a hatter, though his machine eventually works.
- After three sleepless nights, I felt as mad as a hatter and twice as disorganized.
- The old comedy portrays its judge as mad as a hatter, a description that now sounds dated.