Dictionary.com
definitions

color blindness

noun

inability to distinguish one or several chromatic colors, independent of the capacity for distinguishing light and shade.
complete inability to distinguish colors of the spectrum, with all objects appearing as shades of gray, black, and white, varying only as to lightness and darkness; achromatopsia.

Origin of color blindness

First recorded in 1835–45
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Word Origin and History for colorblindness

color blindness

n.

1844, replacing Daltonism (after English chemist John Dalton, 1766-1844, who published a description of it in 1794); in figurative use, with reference to race or ethnicity, attested from 1866, American English. Related: color blind (adj.).

Online Etymology Dictionary, © 2010 Douglas Harper
colorblindness in Medicine

color blindness

n.

Deficiency of color perception, whether hereditary or acquired, partial or complete.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
colorblindness in Culture

colorblindness

A defect in perception of colors, caused by a deficiency of certain specialized cells in the retina that are sensitive to different colors. The condition may be partial (as in “red-green colorblindness,” in which a person cannot distinguish red from green), or complete (in which the person sees all colors as gray).

Note

By extension, the law is said to be colorblind in its judgments, which are supposed to ignore a defendant's race.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.