genus of plants native to Mexico and Central America, 1804, named 1791 by Spanish botanist Antonio José Cavanilles for Anders Dahl (1751-1789), Swedish botanist and pupil of Linnaeus, who discovered it for science in Mexico in 1788.
The likelihood that a true blue variety of the flower never could be cultivated was first proposed by French-Swiss botanist Augustin Pyramus de Candolle, and noted in English by 1835; hence blue dahlia, figurative expression for "something impossible or unattainable" (1843).
precious stone, a blue-to-transparent variety of corundum next in hardness to diamond, mid-13c., saphyr, from Old French saphir (12c.) and directly from Latin sapphirus (source also of Spanish zafir, Italian zaffiro), from Greek sappheiros, name of a blue precious stone, from a Semitic source (compare Hebrew sappir "sapphire"), but according to OED probably not ultimately from Semitic.
Some linguists propose an origin in Sanskrit sanipriya, a dark precious stone (perhaps sapphire or emerald), literally "sacred to Saturn," from Sani "Saturn" + priyah "precious." The gem meant by the Greeks apparently was not the one now so called, but perhaps rather lapis lazuli, the modern sapphire perhaps being signified by Greek hyakinthos. In Renaissance lapidaries, it was said to cure anger and stupidity. As an adjective from early 15c. As a color, a deep brilliant or bright blue, by 1680s. Related: Sapphiric.
"A coarse cotton stuff, generally blue, worn by sailors" [Century Dictionary, 1897], 1610s, dongerijns, from Hindi dungri "coarse calico," said to be from the name of a village, now one of the quarters of Bombay. Dungarees "trousers made of dungaree" is by 1868.
type of plant (in modern use Rubia tinctorum) yielding a valuable dyestuff, Old English mædere and Old Norse maðra, from PIE *modhro- "dye plant" (source also of Old High German matara "madder," Polish modry, Czech modry "blue").
word-forming element used in science for the carbon-nitrogen compound radical, from a Latinized form of Greek kyanos "dark blue" (see cyan).
The immediate source of its use in science is French cyanogène, the name given to the compound radical by Gay-Lussac. He called it that because it first had been obtained by heating the dye pigment powder known as Prussian blue (see Prussian).
The cyanogen radical was one of the first examples of a 'compound radical' and was of importance in the development of structural chemistry during the next forty years. [Flood, "Origins of Chemical Names"]
word-forming element meaning "black," from Greek melano-, combining form of melas (genitive melanos) "black, dark, murky,"probably from a PIE root *melh-"black, of darkish color" (source also of Sanskrit malinah "dirty, stained, black," Lithuanian mėlynas"blue," Latin mulleus "reddish").
mid-15c., "cord, lace, or ribbon of fine material worn as an ornament or token of victory," from Old French cordon "ribbon, cord," diminutive of corde "cord" (see cord). Military sense of "a line of troops or military posts guarding a place" is by 1758.
The original sense is preserved in cordon bleu (1727) "the highest distinction," literally "blue ribbon," for the sky-blue ribbon worn by the old French order of Knights-grand-cross of the Holy Ghost (the highest order of chivalry under the Bourbons). Extended figuratively to other persons of distinction, especially, in jocular use, to a first-rate cook.
Cordon sanitaire (1857) is French, a line of troops or military posts set around an infected district to keep the disease from spreading.