bleakyoudaoicibaDictYouDict[bleak 词源字典]
bleak: [16] Bleak originally meant ‘pale’, and comes ultimately from an Indo-European base *bhleg-, possible source of black and a variant of *phleg-, which produced Greek phlégein ‘burn’ and Latin flagrāre ‘burn’ (whence English conflagration and flagrant; flame, fulminate, and refulgent are also closely related).

From *bhlegcame the prehistoric Germanic adjective *blaikos ‘white’, from which Old English got blāc ‘pale’ (the sense relationship, as with the possibly related blaze, is between ‘burning’, ‘shining brightly’, ‘white’, and ‘pale’). This survived until the 15th century in southern English dialects as bloke, and until the 16th century in the North as blake.

Its disappearance was no doubt hastened by its resemblance to black, both formally and semantically, since both ‘pale’ and ‘dark’ carry implications of colourlessness. Blake did however persist in Northern dialects until modern times in the sense ‘yellow’. Meanwhile, around the middle of the 16th century bleak had begun to put in an appearance, borrowed from a close relative of bloke/blake, Old Norse bleikr ‘shining, white’.

The modern sense ‘bare’ is recorded from very early on. A derivative of the Germanic base *blaikwas the verb *blaikjōn, source of Old English blǣcan ‘whiten’, the ancestor of modern English bleach (which may be related to blight). And a nasalized version of the stem may have produced blink [14].

=> bleach, blight, blink, conflagration, flagrant, flame, fulminate[bleak etymology, bleak origin, 英语词源]
black (adj.)youdaoicibaDictYouDict
Old English blæc "dark," from Proto-Germanic *blakaz "burned" (cognates: Old Norse blakkr "dark," Old High German blah "black," Swedish bläck "ink," Dutch blaken "to burn"), from PIE *bhleg- "to burn, gleam, shine, flash" (cognates: Greek phlegein "to burn, scorch," Latin flagrare "to blaze, glow, burn"), from root *bhel- (1) "to shine, flash, burn;" see bleach (v.).

The same root produced Old English blac "bright, shining, glittering, pale;" the connecting notions being, perhaps, "fire" (bright) and "burned" (dark). The usual Old English word for "black" was sweart (see swart). According to OED: "In ME. it is often doubtful whether blac, blak, blake, means 'black, dark,' or 'pale, colourless, wan, livid.' " Used of dark-skinned people in Old English.

Of coffee, first attested 1796. Meaning "fierce, terrible, wicked" is late 14c. The color of sin and sorrow since at least c. 1300; sense of "with dark purposes, malignant" emerged 1580s (as in black magic). Black face in reference to a performance style originated in U.S., is from 1868. Black flag, flown (especially by pirates) as a signal of "no mercy," from 1590s. Black dog "melancholy" attested from 1826. Black belt is from 1875 in reference to districts of the U.S. South with heaviest African population; 1870 with reference to fertility of soil; 1913 in judo sense. Black power is from 1966, associated with Stokely Carmichael.
acrylamideyoudaoicibaDictYouDict
"A colourless crystalline solid which readily forms water-soluble polymers", Late 19th century: from acrylic + amide.
methylalyoudaoicibaDictYouDict
"Dimethoxymethane, (CH3O)2CH2, a colourless, volatile, pungent liquid, used as a solvent and formerly as an anaesthetic", Mid 19th cent.; earliest use found in Robert Thomson (1810–1864), medical officer of health. From French méthylal or German Methylal, shortened from German Formomethylal from formo- (formo-) + methyl- (in Methylen) + -al (in Acetal).
cyanogenyoudaoicibaDictYouDict
"A colourless flammable highly poisonous gas made by oxidizing hydrogen cyanide", Early 19th century: from French cyanogène, from Greek kuanos 'dark blue mineral' + -gène (see -gen), so named because it is a constituent of Prussian blue.
cryoliteyoudaoicibaDictYouDict
"A white or colourless mineral consisting of a fluoride of sodium and aluminium. It is added to bauxite as a flux in aluminium smelting", Early 19th century: from cryo- 'cold, frost' (because the main deposits are found in Greenland) + -lite.
millefioriyoudaoicibaDictYouDict
"A kind of ornamental glass in which a number of glass rods of different sizes and colours are fused together and cut into sections which form various patterns, typically embedded in colourless transparent glass to make items such as paperweights", Mid 19th century: from Italian millefiore, literally 'a thousand flowers'.
phosgeneyoudaoicibaDictYouDict
"A colourless poisonous gas made by the reaction of chlorine and carbon dioxide. It was used as a poison gas, notably in the First World War", Early 19th century: from Greek phōs 'light' + -gen, with reference to its original production by the action of sunlight on chlorine and carbon monoxide.
butyric acidyoudaoicibaDictYouDict
"A colourless syrupy liquid organic acid found in rancid butter and in arnica oil", Mid 19th century: butyric from Latin butyrum (see butter) + -ic.
rhodiziteyoudaoicibaDictYouDict
"A rare mineral containing boron and beryllium, typically occurring in pegmatites as colourless, white, or yellowish crystals associated with rubellite", Mid 19th cent.; earliest use found in London and Edinburgh Philosophical Magazine. From German Rhodizit from Hellenistic Greek ῥοδίζειν to be rose-like (from ancient Greek ῥόδον rose + -ίζειν) + German -it; so called because it colours the flame of a blowpipe red.
anthraceneyoudaoicibaDictYouDict
"A colourless crystalline aromatic hydrocarbon obtained by the distillation of crude oils and used in chemical manufacture", Mid 19th century: from Greek anthrax, anthrak- 'coal' + -ene.
baryteyoudaoicibaDictYouDict
"A mineral consisting of barium sulphate, typically occurring as colourless prismatic crystals or thin white flakes", Late 18th century (as barytes): from Greek barus 'heavy' + endings based on Greek -ites.
methylamineyoudaoicibaDictYouDict
"Each of the three compounds that can be formed by replacing one or more of the hydrogen atoms in ammonia with a methyl group or groups; especially CH3NH2 (monomethylamine), a colourless, flammable gas with a fishy or ammonia-like odour", Mid 19th cent.; earliest use found in Philosophical Transactions of the Royal Society of London. From French méthylamine from methyl + amine.
chloric acidyoudaoicibaDictYouDict
"A colourless liquid acid with strong oxidizing properties", Early 19th century: chloric from chlorine + -ic.
pyridineyoudaoicibaDictYouDict
"A colourless volatile liquid with an unpleasant odour, present in coal tar and used chiefly as a solvent", Mid 19th century: from Greek pur 'fire' + -ide + -ine4.