show one's hand

show (one's) hand

To make one's plans, intentions, ideas, or resources known to others, especially those that were previously hidden or kept secret. (Also expressed as "show (one's) cards"; both phrases refer to displaying one's cards ("hand") during a card game.) In business negotiations, it's important that you don't show your hand right away, or you might risk losing out on the best deal possible. Pressure from the government is forcing the notoriously secretive CEO to show his hand regarding his company's tax profile and offshore accounts.
See also: hand, show
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

show one's hand

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]
See also: hand, show
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

show one's hand, to

To reveal one’s true motives or intentions. This term, like laying one’s cards on the table, comes from card-playing. Edmund Campion used a version of it in 1581: “I would I might be suffered to shewe my cardes” (Conferences Held in the Tower of London with Ed. Campion, Jesuit, cited by OED). A variant is to tip one’s hand, of the same provenance. The Economist used it on November 17, 1979: “Mr Hunt will not tip his hand on the price at which he will buy more bullion.”
See also: show, to
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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References in periodicals archive ?
Although unwilling to reveal the Council's intentions regarding a bilateral "open sky" pact with the United States - suggesting it would be poor strategy to "show one's hand at this early stage" - Mr Darling described the resumption and conclusion of negotiations with the United States as a "high priority".