tip one’s hand

tip (one's) hand

To reveal one's intentions, plans, secrets, or resources. An allusion to letting someone else see the cards one is currently holding (one's "hand"). The foreign leader has definitely tipped his hand when it comes to his country's position in the negotiations. Remember not to tip your hand when you go into the meeting.
See also: hand, tip

tip one’s hand

tv. to reveal what one is going to do; to reveal one’s secrets. (From card playing.) I didn’t tip my hand at all. I left them guessing.
See also: hand, tip