\ ˈfau̇(-ə)l-ˌəp How to pronounce foul-up (audio) \

Definition of foul-up

 (Entry 1 of 2)

1 : a state of confusion or an error caused by ineptitude, carelessness, or mismanagement foul-ups in transportation
2 : a mechanical difficulty

foul up

fouled up; fouling up; fouls up

Definition of foul up (Entry 2 of 2)

transitive verb

1 : to make dirty : contaminate
2 : to spoil by making mistakes or using poor judgment : confuse
3 : entangle, block fouled up communications

intransitive verb

: to cause a foul-up : bungle it was his fault. He had fouled up— Pat Frank

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Examples of foul-up in a Sentence


tried not to foul up the football play unfortunately, I fouled up and in my e-mail gave everyone the wrong date for the meeting

Recent Examples on the Web: Verb

Got there late, being fouled up en route by getting on wrong tube. Phoebe Wall Howard, Detroit Free Press, "Service Diary of a Corpsman: Roy L. Wall, LST 509," 28 May 2018 Radiation fouled up their microprocessors and camera components. Krista Stevens, Longreads, "Little Sunfish: The Robot That Could," 1 May 2018 And a trade fight between the U.S. jetmaker and Bombardier Inc. threatens to foul up a separate deal that’s key to Delta’s fleet plans. Time, "Delta Is Saying Goodbye to its Boeing 747, the 'Queen of the Skies'," 20 Dec. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'foul-up.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of foul-up


1950, in the meaning defined at sense 1


1947, in the meaning defined at transitive sense 1

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Learn More about foul-up

Dictionary Entries near foul-up

foul strike

foul tip

foul trouble


foul up



Statistics for foul-up

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Time Traveler for foul-up

The first known use of foul-up was in 1947

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More Definitions for foul-up



English Language Learners Definition of foul-up

informal : a problem caused by someone making a mistake or being careless

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More from Merriam-Webster on foul-up

Rhyming Dictionary: Words that rhyme with foul-up

Thesaurus: All synonyms and antonyms for foul-up

Spanish Central: Translation of foul-up

Nglish: Translation of foul-up for Spanish Speakers

Comments on foul-up

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