英语词源字典 - 在线词源网站

detente (n.)[detente 词源字典]: 1908 as a political term, a borrowing of French détente "loosening, slackening" (used in the Middle Ages for the catch of a crossbow), from Vulgar Latin detendita, fem. past participle of Latin detendere "loosen, release," from de- "from, away" (see de-) + tendere "stretch" (see tenet). The reference is to a "relaxing" in a political situation. The French word was earlier borrowed as detent (1680s) "catch which regulates the strike in a clock."[detente etymology, detente origin, 英语词源]
lenient (adj.): 1650s, "relaxing, soothing," from Middle French lenient, from Latin lenientem (nominative leniens), present participle of lenire "to soften, alleviate, mitigate, allay, calm," from lenis "mild, gentle, calm," probably from PIE root *le- "to leave, yield, let go, slacken" (cognates: Lithuanian lenas "quiet, tranquil, tame, slow," Old Church Slavonic lena "lazy," Latin lassus "faint, weary," Old English læt "sluggish, slow," lætan "to leave behind"). Sense of "mild, merciful" (of persons) first recorded 1787. In earlier use was lenitive, attested from early 15c. of medicines, 1610s of persons.
nineties (n.): 1857 as the years of someone's life between 90 and 99; from 1848 as the tenth decade of years in a given century; 1849 with reference to Fahrenheit temperature. See ninety.
Many still live who remember those days; if the old men cannot tell you the exact date, they will say: 'It were in the nineties;' (etc.) ["Chambers's Journal," Nov. 1, 1856]
In Britain, the naughty nineties was a popular name 1920s-30s for the 1890s, based on the notion of a relaxing of morality and mood in contrast to earlier Victorian times. In U.S., gay nineties in reference to the same decade is attested from 1927, and was the title of a regular nostalgia feature in "Life" magazine about that time.
The long, dreary blue-law Sunday afternoons were periods of the Nineties which no amount of rosy retrospect will ever be able to recall as gay, especially to a normal healthy boy to whom all activities were taboo except G. A. Henty and the bound volumes of Leslie's Weekly of the Civil War. [Life, Sept. 1, 1927]
relax (v.): late 14c., "to make (something) less compact or dense," from Old French relaschier "set free; soften; reduce" (14c.), from Latin relaxare "relax, loosen, open, stretch out, widen again; make loose," from re- "back" (see re-) + laxare "loosen," from laxus "loose" (see lax). Of persons, "to become less formal," from 1837. Meaning "decrease tension" is from early 15c.; intransitive sense of "to become less tense" is recorded from 1935. Related: Relaxed; relaxing.