Blunder vs Foul-up

When to use each in English, with meaning, register, and examples.

Blunder

Top 2,000 (common)B1noun

Foul-up

InformalBeyond 10,000 (less common)
Most formal: BlunderMost common: Blunder
 BlunderFoul-up
Pronunciation🇬🇧 //ˈblʌndə//🇺🇸 //ˈblʌndər//🇬🇧 //ˈfaʊlʌp//🇺🇸 //ˈfaʊlˌʌp//
MeaningA big mistake or careless error.To make a mistake or cause a problem.
ExampleHis explanation was full of blunders that made everyone confused.He really had a foul-up during the meeting when he forgot the main points.
RegisterNeutralInformal
How commonTop 2,000 (common)Beyond 10,000 (less common)
CEFR levelB1-
Part of speechnoun
Collocationsserious blunder, common blunder, make a blundermajor foul-up, foul-up a plan, avoid a foul-up, foul-up in communication, classic foul-up
Antonymsaccuracy, perfection, successsuccess, achievement
Common mistakesConfusing with 'fumble' which refers to a physical mistake rather than a mental error., Using 'blunder' only in formal situations; it can also be used in informal contexts., Overusing the word for small mistakes; it's meant for significant errors.Confused with 'foul' as in 'bad' or 'offensive'., Using 'foul-up' in a serious context instead of a light, informal one., Not recognizing 'foul-up' as a verb phrase.
Usage notesUse 'blunder' for mistakes that are noticeable and often embarrassing. It's suitable for most contexts but may sound too strong in casual conversation.Use 'foul-up' informally, often in casual conversation or writing. Avoid in formal contexts or professional settings.

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Blunder
Foul-up

Frequently asked questions: Blunder vs Foul-up

What's the difference between Blunder and Foul-up?

Blunder: A big mistake or careless error. Foul-up: To make a mistake or cause a problem.

Which is more formal: Blunder and Foul-up?

Blunder is the most formal of these.

Which is more common: Blunder and Foul-up?

Blunder is the most common in everyday English.

Can you show an example of each?

Blunder: His explanation was full of blunders that made everyone confused. Foul-up: He really had a foul-up during the meeting when he forgot the main points.

Can I use Blunder and Foul-up interchangeably?

Not always. Blunder and Foul-up are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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