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• foul-up
  foul-up

  noun

  a condition of difficulty or disorder brought on by inefficiency, stupidity, etc.
• foul up
  foul up

  verb

  (tr) to bungle; mismanage

foul-up

American  

[foul-uhp] / ˈfaʊlˌʌp /

noun

Informal.

1. a condition of difficulty or disorder brought on by inefficiency, stupidity, etc.

2. failure of a mechanical part to operate correctly.

3. a person who habitually makes mistakes; bungler.

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foul up British  

verb

1. (tr) to bungle; mismanage

2. (tr) to make dirty; contaminate

3. to be or cause to be blocked, choked, or entangled

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noun

1. a state of confusion or muddle caused by bungling

foul up Idioms  

1. Blunder or cause to blunder; botch, ruin. For example, He's fouled up this report, but I think we can fix it, or Our plans were fouled up by the bad weather. This expression is widely believed to have originated as a euphemism for fuck up. [Colloquial; c. 1940]

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Etymology

Origin of foul-up

1950–55, noun use of verb phrase foul up

Example Sentences

See Examples For:

foul-up foul up

Rumors, recently debunked, spread that the town fired two workers over the foul-up, though neither processed payments.

From The Wall Street Journal ● Jul. 21, 2026

“The reason why you wouldn’t check a bag is that eliminates one of the foul-up points,” Brancatelli said.

From Los Angeles Times ● Nov. 16, 2023

After that, Barney steps way back, and Lee, after a major mission foul-up, is fired by his girlfriend, played by Megan Fox, who takes over the leadership role.

From Seattle Times ● Sep. 22, 2023

Verstappen was winner on merit in Imola and Miami, but in Spain and Monaco Ferrari lost what should have been wins, with an engine failure for Leclerc in Barcelona and a strategy foul-up in Monaco.

From BBC ● Jun. 11, 2022

A mistake, maybe — a foul-up in the paperwork.

From "The Things They Carried" by Tim O'Brien

In the end, though, neither an explosion nor a giant spill of fluid that could foul up waterways and the ocean occurred.

From Los Angeles Times ● May 27, 2026

Self-deleting messages can also foul up long-established record-retention practices and, for some federal employees, they may constitute a violation of the law.

From New York Times ● Jul. 6, 2017

This winter, he says, there’s no El Nino to foul up the weather prognostication.

From Washington Times ● Aug. 14, 2016

We didn't foul up or shrink from the daring option.

From The Guardian ● Jul. 28, 2012

Some inmates, for example, would try to flush something huge, like a bedsheet, in hopes it might foul up the entire block’s plumbing or allow them to flood the gallery.

From "Newjack: Guarding Sing Sing" by Ted Conover