up one's sleeve
Proposed by a contributor, not yet supported by evidence.
Meaning · English
To have a secret plan or surprise in reserve.
Literally: something hidden in one's sleeve
Where it’s used:
Used
Widespread English
Examples
He has a trick up his sleeve to win the competition.
AI-drafted example auto-approved by rule (illustrative, not a corpus attestation)
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 “up one's sleeve” mean?
To have a secret plan or surprise in reserve. Literally: something hidden in one's sleeve
Is “up one's sleeve” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.