crackpot

American  

[krak-pot] / ˈkrækˌpɒt /

noun

1. a person who is eccentric, unrealistic, or fanatical.

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adjective

1. eccentric; impractical; fanatical.

   crackpot ideas.

crackpot British  

/ ˈkrækˌpɒt /

noun

1. an eccentric person; crank

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adjective

1. (usually prenominal) eccentric; crazy

Etymology

Origin of crackpot

First recorded in 1860–65; from the phrase cracked pot

Explanation

A crackpot is a colorfully strange or odd person. You might describe your neighbor as a crackpot if he keeps farm animals inside his house and wears a clown costume everywhere he goes. Although you might call someone a crackpot if he's eccentric or has extreme, unusual beliefs or opinions, the word is fairly derogatory and might offend him. People who are called crackpots often take up unpopular causes or conspiracy theories. A scientist who doesn't believe in the theories of evolution and gravity could be called a crackpot. Dating from the late 19th century, crackpot combines pot, slang for "head," with crack, implying someone whose head is cracked.

Example Sentences

He said crackpot theories have found oxygen in historical amnesia: “If there’s no motive, they can promote their idea that he was just an innocent patsy.”

From Los Angeles Times • Aug. 6, 2025

In the aftermath of his unconventional voyage, Larry Walters assured the American public he wasn't actually a crackpot who had risked life and limb with a hare-brained scheme that was dreamed up on a whim.

From BBC • Apr. 17, 2024

How can someone be both a steel-witted lawyer and a crackpot?

From Slate • Jul. 30, 2023

Scholars studying the conspiracy theories these people fall for sometimes belabor the issue of whether they really "believe" such crackpot notions.

From Salon • May 20, 2023

Is the rule based on some crackpot theory, such as that English should emulate Latin, or that the original meaning of a word is the only correct one?

From "The Sense of Style" by Steven Pinker