show one's hand

1. Reveal one's plans, intentions, or resources, especially when they were previously hidden. For example, We have to be careful not to show our hand to our competitors. The hand here refers to a hand of cards, and showing them means turning them face up. [Late 1800s]

Example Sentences

When the stakes are high and it's time to show one's hand, the people who hold poor cards fold faster than Superman on laundry day.

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To attempt to round De Wet's mobile burghers into this obvious pen would have been to show one's hand too clearly.

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