trick up (one's) sleeve(redirected from a trick up their sleeve)
trick up (one's) sleeve
A secret plan, idea, or advantage that can be utilized if and when it is required. A reference to cheating at a card game by hiding a favorable card up one's sleeve. I've got a few tricks up my sleeve if he decides to pursue legal action against me.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.