faint-hearted (adj.)youdaoicibaDictYouDict[faint-hearted 词源字典]
"cowardly, timorous," c. 1400, from faint (adj.) + hearted. Related: Faint-heartedly; faint-heartedness; faint-heart.[faint-hearted etymology, faint-hearted origin, 英语词源]
faintish (adj.)youdaoicibaDictYouDict
1660s, from faint (adj.) + -ish.
faintly (adv.)youdaoicibaDictYouDict
c. 1300, "dispiritedly, timidly, half-heartedly;" early 14c. "feebly, wearily, without vigor;" from faint (adj.) + -ly (2). Meaning "indistinctly" is from 1580s. Also in Middle English, "deceitfully, hypocritically, falsely" (mid-14c.).
faintness (n.)youdaoicibaDictYouDict
early 14c., "feebleness, weariness," from faint (adj.) + -ness. Meaning "exhaustion" is mid-15c. Of color, light, etc., from 1640s.
fair (adj.)youdaoicibaDictYouDict
Old English fæger "pleasing to the sight (of persons and body features, also of objects, places, etc.); beautiful, handsome, attractive," of weather, "bright, clear, pleasant; not rainy," also in late Old English "morally good," from Proto-Germanic *fagraz (cognates: Old Saxon fagar, Old Norse fagr, Swedish fager, Old High German fagar "beautiful," Gothic fagrs "fit"), perhaps from PIE *pek- (1) "to make pretty" (cognates: Lithuanian puošiu "I decorate").

The meaning in reference to weather preserves the oldest sense "suitable, agreeable" (opposed to foul (adj.)). Of the main modern senses of the word, that of "light of complexion or color of hair and eyes, not dusky or sallow" (of persons) is from c. 1200, faire, contrasted to browne and reflecting tastes in beauty. From early 13c. as "according with propriety; according with justice," hence "equitable, impartial, just, free from bias" (mid-14c.).

Of wind, "not excessive; favorable for a ship's passage," from late 14c. Of handwriting from 1690s. From c. 1300 as "promising good fortune, auspicious." Also from c. 1300 as "above average, considerable, sizable." From 1860 as "comparatively good."

The sporting senses (fair ball, fair catch, etc.) began to appear in 1856. Fair play is from 1590s but not originally in sports. Fair-haired in the figurative sense of "darling, favorite" is from 1909. First record of fair-weather friends is from 1736 (in a letter from Pope published that year, written in 1730). The fair sex "women" is from 1660s, from the "beautiful" sense (fair as a noun meaning "a woman" is from early 15c.). Fair game "legitimate target" is from 1776, from hunting.
Others, who have not gone to such a height of audacious wickedness, have yet considered common prostitutes as fair game, which they might pursue without restraint. ["Advice from a Father to a Son, Just Entered into the Army and about to Go Abroad into Action," London, 1776]
fair (n.)youdaoicibaDictYouDict
"a stated market in a town or city; a regular meeting to buy, sell, or trade," early 14c., from Anglo-French feyre (late 13c.), from Old French feire, faire "fair, market; feast day," from Vulgar Latin *feria "holiday, market fair," from Latin feriae "religious festivals, holidays," related to festus "solemn, festive, joyous" (see feast (n.)).
fair (adv.)youdaoicibaDictYouDict
Old English fægere "beautifully," from fæger "beautiful" (see fair (adj.)). From c. 1300 as "honorably;" mid-14c. as "correctly; direct;" from 1510s as "clearly." Fair and square is from c. 1600. Fair-to-middling is from 1829, of livestock markets.
fair-minded (adj.)youdaoicibaDictYouDict
1754, from fair (adj.) + minded.
fair-spoken (adj.)youdaoicibaDictYouDict
mid-15c.; see fair (adj.) + -spoken.
fairground (n.)youdaoicibaDictYouDict
also fair-ground, 1741, from fair (n.) + ground (n.).
fairing (n.)youdaoicibaDictYouDict
"piece added for streamlining purposes," 1865, from fair (v.) a ship-building word meaning "to make 'fair' or level, adjust, make regular, correct curvatures," from fair (adj.).
fairly (adv.)youdaoicibaDictYouDict
c. 1400, "handsomely," from fair (adj.) + -ly (2). Meaning "impartially, justly" is from 1670s. Sense of "somewhat" is from 1805, a curious contrast to the earlier, but still active, sense of "totally" (1590s). Old English had fægerlice "splendidly."
fairness (n.)youdaoicibaDictYouDict
Old English fægernes "beauty;" see fair (adj.) + -ness. Meaning "even-handedness, impartiality" is from mid-15c. Meaning "lightness of complexion" is from 1590s.
fairway (n.)youdaoicibaDictYouDict
1580s, "navigational channel of a river," from fair (adj.) + way (n.). Golfing sense is by 1898.
fairy (n.)youdaoicibaDictYouDict
c. 1300, fairie, "the country or home of supernatural or legendary creatures; fairyland," also "something incredible or fictitious," from Old French faerie "land of fairies, meeting of fairies; enchantment, magic, witchcraft, sorcery" (12c.), from fae "fay," from Latin fata "the Fates," plural of fatum "that which is ordained; destiny, fate," from PIE *bha- "to speak" (see fame (n.)). Also compare fate (n.), also fay.
In ordinary use an elf differs from a fairy only in generally seeming young, and being more often mischievous. [Century Dictionary]
But that was before Tolkien. As a type of supernatural being from late 14c. [contra Tolkien; for example "This maketh that ther been no fairyes" in "Wife of Bath's Tale"], perhaps via intermediate forms such as fairie knight "supernatural or legendary knight" (c. 1300), as in Spenser, where faeries are heroic and human-sized. As a name for the diminutive winged beings in children's stories from early 17c.
Yet I suspect that this flower-and-butterfly minuteness was also a product of "rationalization," which transformed the glamour of Elfland into mere finesse, and invisibility into a fragility that could hide in a cowslip or shrink behind a blade of grass. It seems to become fashionable soon after the great voyages had begun to make the world seem too narrow to hold both men and elves; when the magic land of Hy Breasail in the West had become the mere Brazils, the land of red-dye-wood. [J.R.R. Tolkien, "On Fairy-Stories," 1947]
Hence, figurative adjective use in reference to lightness, fineness, delicacy. Slang meaning "effeminate male homosexual" is recorded by 1895. Fairy ring, of certain fungi in grass fields (as we would explain it now), is from 1590s. Fairy godmother attested from 1820. Fossil Cretaceous sea urchins found on the English downlands were called fairy loaves, and a book from 1787 reports that "country people" in England called the stones of the old Roman roads fairy pavements.
fairy-tale (n.)youdaoicibaDictYouDict
"oral narrative centered on magical tests, quests, and transformations," 1749, translating French Conte de feés, the name given to her collection by Madame d'Aulnois (1698, translated into English 1699). As an adjective (also fairytale), attested by 1963.
fairyland (n.)youdaoicibaDictYouDict
also fairy-land, 1580s, from fairy + land (n.). Earlier simply Faerie (c. 1300).
fait accompli (n.)youdaoicibaDictYouDict
"a scheme already carried into execution," 19c., French, literally "an accomplished fact." See feat and accomplish.
faith (n.)youdaoicibaDictYouDict
mid-13c., faith, feith, fei, fai "faithfulness to a trust or promise; loyalty to a person; honesty, truthfulness," from Anglo-French and Old French feid, foi "faith, belief, trust, confidence; pledge" (11c.), from Latin fides "trust, faith, confidence, reliance, credence, belief," from root of fidere "to trust," from PIE root *bheidh- "to trust" (source also of Greek pistis "faith, confidence, honesty;" see bid). For sense evolution, see belief. Accomodated to other English abstract nouns in -th (truth, health, etc.).

From early 14c. as "assent of the mind to the truth of a statement for which there is incomplete evidence," especially "belief in religious matters" (matched with hope and charity). Since mid-14c. in reference to the Christian church or religion; from late 14c. in reference to any religious persuasion.
And faith is neither the submission of the reason, nor is it the acceptance, simply and absolutely upon testimony, of what reason cannot reach. Faith is: the being able to cleave to a power of goodness appealing to our higher and real self, not to our lower and apparent self. [Matthew Arnold, "Literature & Dogma," 1873]
From late 14c. as "confidence in a person or thing with reference to truthfulness or reliability," also "fidelity of one spouse to another." Also in Middle English "a sworn oath," hence its frequent use in Middle English oaths and asseverations (par ma fay, mid-13c.; bi my fay, c. 1300).
faith-healer (n.)youdaoicibaDictYouDict
Also faith healer, attested by 1874; from faith + healer. Faith-curer is from 1883.
The power which a man's imagination has over his body to heal it or make it sick is a force which none of us is born without. The first man had it, the last one will possess it. If left to himself, a man is most likely to use only the mischievous half of the force--the half which invents imaginary ailments for him and cultivates them; and if he is one of those very wise people, he is quite likely to scoff at the beneficent half of the force and deny its existence. [Mark Twain, "Christian Science," 1907]