out to lunch
Proposed by a contributor, not yet supported by evidence.
Meaning · English
completely wrong or mistaken
Literally: eating lunch away from a normal location
Where it’s used:
Used
Widespread English
Examples
‘ I think he's finally out to lunch.
Nigel knockers are out to lunch
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. Definition drafted by AI (@cf/meta/llama-3.3-70b-instruct-fp8-fast) and auto-approved by rule on 2026-07-31; pending editor spot-check.
Common questions
What does “out to lunch” mean?
completely wrong or mistaken Literally: eating lunch away from a normal location
Is “out to lunch” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.