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Mad as a hatter

“Mad as a hatter” is a humorous idiom used to refer to someone who is completely crazy.

Such a person tends to also be someone who has gone past the point of no return.

“Mad as a hatter” is a popular and historically complex idiom that is quite well-known. The phrase is commonly connected to Lewis Carroll’s Alice’s Adventures in Wonderland. As an idiom, “mad as a hatter” is a phrase that requires context to make sense of it. Without understanding that context, the idiom does not make sense. This is why idioms are challenging for new English speakers to understand.

What does "Mad as a Hatter" Mean? Origins, Definition and Examples


Meaning of “Mad as a hatter”

Unlike many idioms, this one’s meaning is fairly straightforward, at least in part. The first three words, “Mad as a,” reveal to the listener/reader that the person to whom the words are directed is considered “mad” or crazy. The “hatter” part of the idiom is slightly more complicated. It relates to the hat-making industry of the 18th and 19th centuries and the effects of mercury poisoning.


Origins of “Mad as a hatter”

The phrase “Mad as a hatter” is commonly misattributed to Lewis Carroll’s novel Alice’s Adventures in Wonderland. In truth, it has much more complicated and more interesting origins. The expression is linked to the hat-making industry and the terrible consequences of mercury poisoning. The material was used for years before anyone became aware of its toxic properties. It was used every day as part of the process of turning animal furs into hats.

Mercury poisoning and bring on physical and mental problems that manifest as speech problems and hallucinations. Symptoms that would’ve seemed like madness in the 1800s.

Some scholars have suggested that the originator of the “mad hatter’ phrase might’ve been D.C. Corbett, famed for his killing of John Wilkes Booth after the assassin shot Abraham Lincoln. Corbett worked in a hat factory prior to joining the Union Army during the Civil War. His regiment was assigned to track down the booth and eventually found him in a barn in Virginia. He disobeyed his orders and shot and killed Booth rather than capturing him.

There are moments of record in his life that might’ve hinted at some mental instability that could’ve been related to mercury poisoning. This included an incident before the war, where he castrated himself with a pair of scissors. After his brief moment of fame, he was admitted to a mental asylum after threatening people with a gun. He eventually escaped, and no further records of his life exist. While it is not confirmed, this is one popular theory in regards to where the phrase came from.


When to Use “Mad as a hatter”

The best examples of this phrase originated with Alice in Wonderland and Lewis Carroll’s famed character, the Hatter. He’s referred to as “mad” throughout the story and later came to be referred to simply as the “Mad Hatter.” If you want to use this phrase in a sentence, whether spoken allowed or in writing, it is important to know that it is considered to be more humorous than it is serious. You wouldn’t use it when confronting someone you think is out of line. Although not always, it’s more likely said in jest when someone you know is acting unusually or excitedly.


Example Sentences with “Mad as a hatter”

  • I couldn’t believe how he was acting. He was mad as a hatter.
  • Her mother was mad as a hatter.
  • I was acting mad as a hatter until I knew we were safe.


Why Do Writers Use “Mad as a hatter?”

The idiom “mad as a hatter” is not a commonly used phrase in writing. This is due mostly to the direct link it has to Lewis Carroll’s Alice’s Adventures in Wonderland. A writer would be unable to use these four words without drawing a direct comparison to Carroll’s writing. This might, in some circumstances, such as in a character’s dialogue, be useful. But, most of the time, writers will want to avoid these kinds of associations if possible. The idiom is more often used in playful speech than it is in writing.


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