Definition of up one's sleeve in US English:

up one's sleeve

phrase

  • (of a strategy, idea, or resource) kept secret and in reserve for use when needed.

    ‘he was new to the game but had a few tricks up his sleeve’
    • ‘He said he has a secret sound effect up his sleeve to accompany a flash of lightning but the audience will have to wait and see how this is accomplished.’
    • ‘Your hand will reveal who you are - and what tricks you may have up your sleeve…’
    • ‘Lubar has several successful strategies up his sleeve that keep us laughing.’
    • ‘They will also have a few tricks up their sleeve and perhaps change the way they play to catch us out this week.’
    • ‘Annie puts her success down to eating wholesome, home-cooked food, while Dorothy has another secret up her sleeve.’
    • ‘I'll bet you're sitting there with a thousand ideas up your sleeve.’
    • ‘I still have a few ideas up my sleeve, which will inevitably disappoint some readers and please others.’
    • ‘Do you have any tricks up your sleeve to give business spending a boost?’
    • ‘‘At the same time, we needed to have a few tricks up our sleeve to surprise the audience,’ he says.’
    • ‘There are still some ideas up my sleeve - including book lists to be added to the library.’