fairy (n.) Look up fairy at Dictionary.com
c.1300, fairie, "enchantment, magic," from Old French faerie "land of fairies, meeting of fairies, enchantment, magic," from fae "fay," from Latin fata (plural) "the Fates," from PIE *bha- "to speak" (see fame (n.)).

As "a supernatural creature" 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" (early 14c.). The diminutive winged beings so-called in children's stories seem to date 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]
The slang meaning "effeminate male homosexual" is first recorded 1895. Fairy ring is from 1590s. Fossil sea urchins found on the English downlands were called fairy loaves.