late 14c., colouren, "to make (something) a certain color, to give or apply color to," also figurative "to use (words) to a certain effect; to make (something) appear different from reality or better than it is," from Old French culurer, colorer, and directly from Latin colorare, from color (see color (n.)). Intransitive sense "become red in the face" is from 1721. Related: Colored; coloring.
early 13c., "skin color, complexion," from Anglo-French culur, coulour, Old French color "color, complexion, appearance" (Modern French couleur), from Latin color "color of the skin; color in general, hue; appearance," from Old Latin colos, originally "a covering" (akin to celare "to hide, conceal"), from PIE root *kel- (1) "to cover, conceal, save." Old English words for "color" were hiw ("hue"), bleo. For sense evolution, compare Sanskrit varnah "covering, color," which is related to vrnoti "covers," and also see chroma.
Colour was the usual English spelling from 14c., from Anglo-French. Classical correction made color an alternative from 15c., and that spelling became established in the U.S. (see -or).
Meaning "a hue or tint, a visible color, the color of something" is from c. 1300. As "color as an inherent property of matter, that quality of a thing or appearance which is perceived by the eye alone," from late 14c. From early 14c. as "a coloring matter, pigment, dye." From mid-14c. as "kind, sort, variety, description." From late 14c. in figurative sense of "stylistic device, embellishment. From c. 1300 as "a reason or argument advanced by way of justifying, explaining, or excusing an action," hence "specious reason or argument, that which hides the real character of something" (late 14c.).
From c. 1300 as "distinctive mark of identification" (as of a badge or insignia or livery, later of a prize-fighter, horse-rider, etc.), originally in reference to a coat of arms. Hence figurative sense as in show one's (true) colors "reveal one's opinions or intentions;" compare colors.
In reference to "the hue of the darker (as distinguished from the 'white') varieties of mankind" [OED], attested from 1792, in people of colour, in translations from French in reference to the French colony of Saint-Domingue (modern Haiti) and there meaning "mulattoes."
In reference to musical tone from 1590s. Color-scheme is from 1860. Color-coded is by 1943, in reference to wiring in radios and military aircraft. Color-line in reference to social and legal discrimination by race in the U.S. is from 1875, originally referring to Southern whites voting in unity and taking back control of state governments during Reconstruction (it had been called white line about a year earlier, and with more accuracy).
also colour-blindness, "incapacity for perceiving certain colors due to an absence or weakness of the sensation upon which the power of distinguishing them depends," 1844, the native word, used in England instead of French daltonisme (by 1828), after English chemist John Dalton (1766-1844), who published a description of it in 1794. From color (n.) + blindness.
The continental philosophers have named it Daltonism, a name which has been strongly objected to by almost every English writer who has discussed the subject, on the ground of the inexpediency and undesirableness of immortalizing the imperfections or personal peculiarities of celebrated men by title of this kind. ... The name "Color-Blindness," proposed by Sir D. Brewster, seems in every respect unexceptionable. [Littell's Living Age, vol. v, April 1845]
Noted as inexact (very few people who can see are blind to all color), "the term is applied with much laxity to any constitutional inability to discriminate between colours" [OED]. In figurative use, with reference to race or ethnicity, it is attested from 1866, American English. Related: color-blind (adj.), which is attested from 1854.