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Related to hatter: hater, Alice

be (as) mad as a hatter

1. To be crazy. Tim has been behaving very erratically lately, so I'm afraid that he's as mad as a hatter.
2. To be very angry. Mom was mad as a hatter after I dented her brand-new car.
See also: hatter, mad

*mad as a hatter

 and *mad as a march hare 
1. crazy. (Alludes to the crazy characters in Lewis Carroll's Alice's Adventures in Wonderland. *Also: as ~.) Poor old John is as mad as a hatter. All these screaming children are driving me mad as a hatter.
2. angry. (This is a misunderstanding of mad in the first sense. *Also: as ~.) You make me so angry! I'm as mad as a hatter. John can't control his temper. He's always mad as a hatter.
See also: hatter, mad

mad as a hatter

Also, mad as a March hare. Crazy, demented, as in She is throwing out all his clothes; she's mad as a hatter. This expression, dating from the early 1800s, alludes to exposure to the chemicals formerly used in making felt hats, which caused tremors and other nervous symptoms. The variant, dating from the 14th century, alludes to the crazy behavior of hares during rutting season, mistakenly thought to be only in March.
See also: hatter, mad

mad as a hatter

mainly BRITISH
If someone is as mad as a hatter, they are crazy. Her sister's as mad as a hatter and if you ask me she's not much better herself. Note: In the 19th century, `hatters' or hat-makers used nitrate of mercury to treat their fabrics. This substance is poisonous, and if the hat-makers breathed it in, they often suffered brain damage. As a result, hatters were traditionally thought of as mad. In Lewis Carroll's children's story `Alice in Wonderland' (1865), one of the characters is a hatter who behaves very strangely. Carroll may have based the character on a well-known Oxford furniture dealer, Theophilus Carter, who was known as the `Mad Hatter'.
See also: hatter, mad

mad as a hatter (or a March hare)

completely crazy. informal
In this expression, a hatter refers to Lewis Carroll's character, the Mad Hatter, in Alice's Adventures in Wonderland ( 1865 ). It is thought that hatters suffered from the effects of mercury poisoning because of the fumes arising from the use of mercurous nitrate in the manufacture of felt hats. The March hare version refers to the way hares leap about during the breeding season.
See also: hatter, mad

(as) mad as a ˈhatter

(informal) (of a person) crazyThe Mad Hatter was a character in Lewis Carroll’s Alice’s Adventures in Wonderland. Because of the chemicals used in hat-making, workers often suffered from mercury poisoning, which can cause loss of memory and damage to the nervous system.
See also: hatter, mad

mad as a hatter

Crazy. The standard explanation comes from the effect to the brain caused by mercury nitrate used by 18th- and 19th-century hatmakers. Another view holds that “mad” originally meant “poisonous” and “hatter” is a corruption of the Saxon word “atter,” the adder snake, the bite of which affects the brain. In any event, the Mad Hatter character in Lewis Carroll's Alice in Wonderland is a testimony to eccentricity bordering on madness.
See also: hatter, mad
References in periodicals archive ?
WELSH recruitment agency Smart Solutions has raised more than PS8,000 by hosting a Mad Hatters Ball, in support of their nominated charity Bobath Children's Therapy Centre Wales.
secretary of education under President Jimmy Carter, had argued there were no constitutional violations in this case that gave either Bliss or Hatter authority to make management decisions for the MTA, a public agency.
Both Da Hatter and Tyrur Quinn had been drawn to run in the second heat on Saturday and this means it will be a fourdog race.
Hatter is convinced that if the wipes are in a convenient location, such as being housed within the toilet paper roll, sales of wipes will soar.
It was a thoroughly positive presentation," said Hatter of Saturday's meeting.
Here is a puzzle for you to try: If the Hatter moved on three places at a time, starting his count at one, for a table initially having nine clean place settings, what would be the last clean place setting?
Which means Hatter could end up taking control of this hopeless mess.
Mr Hatter - once described by Mr Blair as a "thoroughly decent bloke" - has a personal fortune of more than pounds 50million from his north London business, which markets electronics components.
This year, the Easter activities were even more special, with the appearance of the official Alice from the Lewis Carroll Society, the Mad Hatter and the Queen of Hearts.
A lot of them, if you're a Red Hatter," said Judy Halligan, also a member of the Red Hot Buddies.
District Court Judge Terry Hatter said he will issue a ruling by Oct.
Teresa Hatter, 51, was driving a 1965 Datsun truck east on West 11th Avenue.
The National Division Two club will hope the appointment of Keith Hatter to their new coaching team will bring a change in fortunes.
The hat makers, called hatters, became ill and went crazy, thus the term "mad as a hatter.
Merlen and Maryon Hatter first met as deckhands on a 100-foot sailboat, cruising-from Florida to the Bahamas through the Panama Canal and on to Hawaii.