blow someone's cover

Proposed by a contributor, not yet supported by evidence.

Meaning · English

Recognized English idiom; full definition pending editorial review.

Where it’s used: Used Widespread English

Examples

One mistake could blow his cover and ruin years of careful work in the North.
And after such a lengthy period of secrecy, was Lucy going to blow her cover so comprehensively in a single gesture?

British National Corpus sentence via the MAGPIE corpus (CC BY 4.0, retrieved 2026-07-30)

Sources & notes

Listed in Wiktionary’s “English idioms” category (retrieved 2026-07-29); definition pending editorial review.

Common questions

What does “blow someone's cover” mean?

Recognized English idiom; full definition pending editorial review.

Is “blow someone's cover” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.