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mad hatter disease

mad hatter disease noun: erethism (neurological disorder from mercury poisoning).

Noun

mad hatter disease (uncountable)

  1. erethism (neurological disorder from mercury poisoning)

Origin of mad hatter disease

"During the 18th to 20th centuries, hat makers used mercury to stiffen felt for hats. They used a type of mercury called mercuric nitrate and worked in poorly ventilated rooms. Over time, the hatters inhaled mercury vapors. Many developed symptoms of chronic mercury poisoning, including psychosis, excitability, and tremors. These symptoms became so common in hatters that the phrase “mad as a hatter” was born."

Questions about mad hatter disease

What does mad hatter disease mean?
Mad hatter disease means erethism (neurological disorder from mercury poisoning).
What part of speech is mad hatter disease?
Mad hatter disease is a noun.

Words near mad hatter disease in the dictionary

  1. mad dogs
  2. mad dogs and Englishmen
  3. mad enough to chew nails
  4. mad for it
  5. mad hatter
  6. mad hatter disease
  7. mad hatter syndrome
  8. mad hatters
  9. mad honey
  10. mad itch
  11. Mad King George

Source and license

Adapted from Wiktionary: mad hatter disease (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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