ace up (one's) sleeve

ace 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. My stamina is the ace up my sleeve for this race—the other runners don't stand a chance! The defense attorney waited for just the right time to play the ace up her sleeve—a new eye-witness.
See also: ace, sleeve, up
Farlex Dictionary of Idioms.
See also:
  • a card up (one's) sleeve
  • card up one's sleeve
  • have a card up (one's) sleeve
  • have a trick up (one's) sleeve
  • have an ace up (one's) sleeve
  • have an ace/a trick up your sleeve
  • have something up your sleeve
  • have up sleeve
  • have/keep something up your sleeve
  • trick up (one's) sleeve