an ace up your sleeve

成語所屬單字sleeve

an ace up your sleeve — 慣用語

1. A hidden advantage or secret resource that you can use when needed.

1.慣用語
釋義

祕密王牌

A hidden advantage or secret resource that you can use when needed.

例句

Maya kept an ace up her sleeve for the final negotiation.

Does Brian have an ace up his sleeve to win the game?