give the game away

present singular third person gives the game away · participle present giving the game away · past gave the game away · participle past given the game away

1. idiomaticTo mistakenly reveal a secret.

   You don't want to mention the money involved; that would give the game away.

   1 more example

   Just as the fearsome prison guard Mr Swivel was becoming more and more suspicious as to why these two had been under the table for so long, Flip slid up on to Dad’s chair. Without her glasses and wearing Dad’s prison overalls, she passed rather well for her nephew. Next, Dad slid up on to Flip’s chair. The boy had to stifle a giggle at the sight of his dad wearing one of Flip’s famous floaty dresses. The glasses softened his face, and from a distance he might just pass as the elderly librarian. “Stop giggling, mate!” hissed Dad. “You’ll give the game away.”

   2017, David Walliams [pseudonym; David Edward Williams], Bad Dad, London: HarperCollins Children’s Books, →ISBN