1 C1 idiomatic slang
To reveal or expose someone's secret, plan, or deception, either accidentally or deliberately.
"He nearly gaffed off their whole operation by mentioning the warehouse in front of the wrong person."
separable
gaff off
C1 slang separable transitive
British slang meaning to inadvertently or deliberately reveal someone's secret, expose their deception, or 'blow someone's cover'.
In plain English
To accidentally or deliberately reveal someone's secret or catch them out.
What does "gaff off" mean?
One main meaning — here's how to use it.
Usage tip
Derives from 'gaff', a British slang word for a mistake or blunder (also 'blow the gaff' = reveal a secret). 'Gaff off' as a phrasal verb is rare and largely restricted to certain British regional or subcultural dialects. 'Blow the gaff' is a more widely recognised equivalent.
Words that pair with "gaff off"
Natural word combinations native speakers use most often.
accidentally nearly somebody the plan the whole operation
How to conjugate "gaff off"
The five tense forms you'll use most often.
Base
gaff off
I/you/we/they
3rd person
gaffs off
he/she/it
Past simple
gaffed off
yesterday
Past participle
gaffed off
have + pp
-ing form
gaffing off
continuous
Hear "gaff off" in the wild
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Other ways to say "gaff off"
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