dead giveaway

a dead giveaway

A clue, detail, action, etc. that obviously reveals something else. Your shoes are totally sticking out of the blankets! That's a dead giveaway that you're planning on sneaking out as soon as mom says good night to us. The homemade card was a dead giveaway that they had forgotten to buy us a gift.
See also: dead, giveaway
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

dead giveaway

something that reveals a fact or an intention completely. The car in the driveway was a dead giveaway that someone was at home.
See also: dead, giveaway
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
CARNIVOR ZINFANDEL 2017, CALIFORNIA, USA (PS10, TESCO) The name's a dead giveaway and if you've never sinned with zin, this is the red to lock you in.
The camera system at the back is also described as "likely a dead giveaway" that it is fake.
Perfect with a simple | Carnivor Zinfandel 2017, California, USA (PS10, Tesco) THE name's a dead giveaway and if you've never sinned with zin, this is the red to lock you in.
Perfect with a simple |California, USA (PS10, Tesco) THE name's a dead giveaway and if you've never sinned with zin, this is the red to lock you in.
The addition of "HH" at the end of most sentences is another dead giveaway.
THANKS TO SEAN HOWARD for highlighting the WWI Canadian battle for Mons, (April Issue #3, "Dead Giveaway, The Dark Side of the Mons Centenary"), but I must take exception with the tone of his 3-page article dubiously entitled "Dead Giveaway" in your April 2019 edition.
For years, archaeologists wondered what these containers held, even though the poppy-seed head was a dead giveaway.
Alejano meanwhile said the June inflation, which pushed the year-to-date figure to 4.3 percent, was "a dead giveaway" Duterte's economic managers were "losing control" over the country's economic fundamentals because of the TRAIN law.
While the photo is a dead giveaway for the diehard fans of the movie, Prats stated that her birthday celebration on the talk show 'Mars', which will air on Monday, June 25, will include guests that have 'something to do with the movie.'
The trick is to stick to neutral colours and size up, sparing use of fabric is a dead giveaway of a cheap copy.
Firm back soil around newly planted trees and shrubs if they have been lifted by winds - loose soil around the trunk is a dead giveaway.
However, the Tupperware can be a dead giveaway that he may still live at home with mom.
You would have thought the positioning of the 'O' in his surname would have been the dead giveaway (he obviously should have played for Italy).
SEEING the name Sebastian Soderberg heading Top Scandinavian betting is a dead giveaway that all the best Swedes and Danes are staying put after their home game in Malmo last week.