false colors

American  

plural noun

1. the flag of a country other than one's own, especially when used deceptively.

   sailing under false colors.

2. false or deceptive actions or statements; misrepresentation.

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false colors Idioms  

1. Pretense, misrepresentation, or hypocrisy; deceptive statements or actions. For example, She's sailing under false colors—she claims to be a Republican, but endorses Democratic legislation. This term alludes to the practice of pirate ships sailing under false colors —that is, running a particular flag specifically to lure another vessel close enough to be captured. [Late 1600s]

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Etymology

Origin of false colors

1565–75, for literal sense

Example Sentences

She is, to be strictly honest, traveling under false colors; G.I.

From Time Magazine Archive

He promptly hoisted the French flag and under these false colors sailed boldly past the British war boats guarding Gibraltar into the Mediterranean.

From Time Magazine Archive

The action of the book moves about the peeling off, in successive layers, of Waring's false colors.

From Time Magazine Archive

Was that because he flew false colors himself?

From Time Magazine Archive

He hoped, too, and trembled while the thought flitted through his mind, that no one in the room would speak his name, for it was his turn to sail under false colors now.

From Rodney The Partisan by Castlemon, Harry