Idiom

ace up your sleeve

idiom (noun phrase) C1

UK /ˌeɪs ʌp jɔː ˈsliːv/

US /ˌeɪs ʌp jʊr ˈsliːv/

Meanings

idiom (noun phrase)

A hidden advantage, resource, or plan that can be used later to gain an edge.

Definition

An ace up your sleeve is a secret advantage or hidden plan you can use when you need it.

An ace up your sleeve is something you keep hidden that will help you succeed later. It can be a clever idea, a useful resource, or a surprise move you do not reveal until the right moment. People often use it when they want to be prepared for problems or competition.

Examples

I thought we had no options, but I had an ace up my sleeve: a contact who could solve the issue overnight.
You say you’re not worried, so I’m guessing you’ve got an ace up your sleeve for the final presentation.
He seemed unprepared in the discussion, yet he had an ace up his sleeve and unveiled decisive evidence at the end.
She kept an ace up her sleeve by rehearsing a backup demo in case the live system failed.
They acted as if the negotiations were stalled, but they had an ace up their sleeve and proposed a creative compromise.

Common mistake

Learners often say “an ace in your sleeve,” but the usual idiom is “an ace up your sleeve.”