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

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

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

From Time Magazine Archive

O'Brian was fascinated with feints and deceptions, with warships that disguise themselves or fly false colors.

From Time Magazine Archive

Was that because he flew false colors himself?

From Time Magazine Archive

Finding nothing in the illustrations that he could criticise, he accused Gibson of sailing under false colors and claiming credit for results that were not of his creation.

From Recollections of a Varied Life by Eggleston, George Cary