Definition of keep something under one's hat in US English:

keep something under one's hat

phrase

  • Keep something a secret.

    • ‘I know how to keep my politics under my hat for a dinner party.’
    • ‘At the moment it's all a bit hush-hush, so keep it under your hat.’
    • ‘Here's a tip for Ascot, but keep it under your hat!’
    • ‘I've been keeping some exciting news under my hat for the past two weeks.’
    • ‘It was difficult for Weber to keep the discovery under his hat.’
    • ‘They've certainly kept this change under their hat.’
    • ‘Churchill replied: ‘I'll tell you a secret, but keep it under your hat.’’
    • ‘I've spoken with him myself on his motives for committing his crime, and while I agreed to keep his explanation under my hat, I firmly believe his actions were justified.’
    • ‘If you've got a good idea, keep it under your hat.’
    • ‘The good folk of Harrogate would not want it shouting from their elegant Georgian rooftops, so keep it under your hat.’
    conceal, hide, cover up, disguise, dissemble, mask, veil
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