Keep something up one's sleeve
Meaning
To have a secret plan, advantage, or resource concealed and ready to be used when the time is right.
Origin
Picture the smoky, hushed gaming parlors of centuries past. A card sharp, with a deceptive smile, appears to play an honest game, but his loose sleeves conceal more than just his arms. With practiced sleight of hand, a crucial ace or a game-changing card could be produced at the opportune moment, turning the tide of the game. This cunning act of literal concealment to gain an unfair advantage cemented the phrase, extending it beyond the card table and the magician's stage to describe any secret plan or hidden resource held in reserve for a strategic reveal.
Examples
- The chess master always keeps a unique opening strategy up his sleeve for important tournaments.
- Don't worry, if this negotiation falls through, I've got a backup offer kept up my sleeve.