behind closed doors
Proposed by a contributor, not yet supported by evidence.
Where it’s used:
Used
Widespread English
Examples
Certainly the opening up of knowledge about finance does enable all heads of faculty to have an organisation - wide view rather than bidding behind closed doors.
Thierse called upon the SPD to act more as the party of the opposition in Bonn, saying that the SPD must not leave the impression of dealing behind closed doors with the federal government.
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. Figurative class: Metaphor (PIE-English corpus, CC BY 4.0, retrieved 2026-07-31).
Common questions
What does “behind closed doors” mean?
In secrecy.
Is “behind closed doors” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.