If someone says you are mad as a hatter, they are accusing you of being quite irrational. The sense of madness here is "suffering from a disorder of the mind; insane." This phrase usually refers not to someone who is actually insane, but rather to a more normal person who is behaving in an irrational way.
The phrase emerged in England in the 19th century. Hatmakers in those days used a lot of felt that was treated with chemicals including lead, arsenic, and mercury.
Unfortunately, those chemicals are highly toxic. The symptoms of such poisoning include palsy, confused speech, and distorted thinking. Today, making hats is a much safer profession, but the phrase survives.
An interesting alternate explanation of the phrase derives hatter from Anglo-Saxon atter (poison), which is related to adder (a poisonous snake whose bite was thought to cause insanity).
by Its me, its me, the M-E-T-Z! December 9, 2003
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This goes back to the time when the people in the hat industry wound up with mercury poisoning due to the process of manufacturing the felt for hats.
He is as mad as a hatter,
by WDD2 April 28, 2016
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"...back to back hits of that Mad Hatter magic."
"Spiders in the mattress, paisley sunglasses, dialated eyes green, Ice grill that could burn through your Picture-in-picture widescreen.
Poison late late show starring Aes Aesop Rock and his jigsaw face."
by bigshady September 3, 2006
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An extremely ugly person, usually of Middle Eastern descent, with a large nose who is totally mad and likely to blow your ass up with some jihad shit.
Osama bin Laden is one mad hatter ass motherfucker!
by panda, the holy warrior October 20, 2006
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Someone with great skills in a craft in which they specify. Many times used as a sports team name because of the definition. The image of the mad hatter team symbol usually shows a large, angry, and muscular man resembling 'Uncle Sam' the mascot of America.
The Mad Hatters defeated the Knights because of their honed skills and prowess upon the field.
When he is in a conversation he is a Mad Hatter, his words are so finely selected and so high class everyone who hears him feels his influence.
by The-MaD-HaTTeR April 4, 2009
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A poorly performed handjob. Usually by a girl who says she is experienced. Yet, in actuality, she jerks you off like a crazed sea dragon.
Yo, bitch, what the fuck are you going all mad hatter for? Tighten that grip up and fuckin quit pullin the shit outta it!
by deal with it May 12, 2006
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