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definitions

false color

noun

photography using infrared-sensitive film that produces images in which heat-emitting areas or objects appear red.

Origin of false color

First recorded in 1965–70
Related formsfalse-col·or, adjective

false colors

plural noun

the flag of a country other than one's own, especially when used deceptively: sailing under false colors.
false or deceptive actions or statements; misrepresentation.

Origin of false colors

1565–75, for literal sense
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Idioms and Phrases with false color

false colors

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]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.