to blow the gaff
Preserved but no longer current.
Meaning · English
To let out a secret; to inform against a companion; to "peach." Here gaff is a variant of gab (#.v.).
Era: ca. 1898 (Victorian)
Sources & notes
Reproduced from Brewer’s Dictionary of Phrase and Fable (1898 edition, public domain; archive.org, retrieved 2026-07-31; OCR text, minor errors possible). Reflects the scholarship and attitudes of its era.
Common questions
What does “to blow the gaff” mean?
To let out a secret; to inform against a companion; to "peach." Here gaff is a variant of gab (#.v.).
Is “to blow the gaff” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.