English

Noun

dead giveaway ‎(plural dead giveaways)

1. (idiomatic) Something that discloses, usually unintentionally, a fact or an intention.

   That disguise is a dead giveaway! Choose something less obvious.

   • 2008, New York Times, March 5

     "Instead of slowing down his arm when he throws it — a dead giveaway to hitters — Igawa had better arm action, Eiland said"

See also

• tell (noun)