beauty (n.)
early 14c., "physical attractiveness," also "goodness, courtesy," from Anglo-French beute, Old French biauté "beauty, seductiveness, beautiful person" (12c., Modern French beauté), earlier beltet, from Vulgar Latin bellitatem (nominative bellitas) "state of being handsome," from Latin bellus "pretty, handsome, charming," in classical Latin used especially of women and children, or ironically or insultingly of men, perhaps from PIE *dw-en-elo-, diminutive of root *deu- "to do, perform, show favor, revere" (see bene-). Famously defined by Stendhal as la promesse de bonheur "the promise of happiness."
[I]t takes the one hundred men in ten million who understand beauty, which isn't imitation or an improvement on the beautiful as already understood by the common herd, twenty or thirty years to convince the twenty thousand next most sensitive souls after their own that this new beauty is truly beautiful. [Stendhal, "Life of Henry Brulard"]
Replaced Old English wlite. Concrete meaning "a beautiful woman" is first recorded late 14c. Beauty sleep "sleep before midnight" is attested by 1850. Beauty spot is from 1650s. Beauty parlor is from 1894.
The sudden death of a young woman a little over a week ago in a down-town "beauty parlor" has served to direct public attention to those institutions and their methods. In this case, it seems, the operator painted on or injected into the patron's facial blemish a 4-per-cent cocaine solution and then applied an electrode, the sponge of which was saturated with carbolized water. ["The Western Druggist," October 1894]
Beauté du diable (literally "devil's beauty") is used as a French phrase in English from 1825.