sweatshop (n.)

c. 1300, "booth or shed for trade or work," perhaps from Old English scoppa, a rare word of uncertain meaning, apparently related to scypen "cowshed," from Proto-Germanic *skoppan "small additional structure" (source also of Old High German scopf "building without walls, porch," German dialectal Scopf "porch, cart-shed, barn," German Schuppen "a shed"), from a root *skupp-. Or the Middle English word was acquired from Old French eschoppe "booth, stall" (Modern French échoppe), which is a Germanic loan-word from the same root.

The meaning "building or room set aside for sale of merchandise" is from mid-14c. The meaning "schoolroom equipped for teaching vocational arts" is from 1914, American English (as in shop class, attested by 1948).

The sense of "one's own business, craft, or calling" is from 1814, as in talk shop (v.), "converse in general society about matters pertaining to one's trade," which is attested in this sense by 1847. Shop-talk (n.) is by 1881.

Lawyers, I am happy to say, seldom talk shop to each other. I have a notion that if they did, they would mutually send each other small bills for opinion and advice given ; and then go into court to have a fair stand-up battle for the thirteen-and-four-pences. [Angus B. Reach, "The Natural History of Humbugs," 1847]

Middle English sweten, from Old English swætan "perspire, excrete moisture from the skin," also "toil, labor, work hard," from Proto-Germanic *swaitjan "to sweat," from the source of sweat (n.). Compare Frisian swette, Dutch zweeten, Danish svede, German schwitzen.

The meaning "be worried, vexed" is recorded from c. 1400. The transitive sense of "cause to excrete moisture" is from late 14c. Related: Sweated; sweating.

1520s, "one who works hard;" 1550s, "one who perspires," agent noun from sweat (v.). From 1680s as "a sudorific, that which causes to sweat." Also in 18c. colloquial use, "street ruffian who bullies by violent intimidation" (1712). It is attested by 1843 as "one who exacts hard work at very low wages, one who overworks and underpays" (see sweatshop).

As "woolen vest or jersey," by 1882, originally worn by rowers in training, from earlier sweaters "clothes worn (by a man or horse) to produce sweating and reduce weight" (1828), plural agent noun from sweat (v.).

As a fashion garment for women, it seems to have been established by 1920, after the lifting of wartime restrictions. Sweater girl is attested by 1939, a studio-nickname for Lana Turner (1920-1995), from her brief appearance at 16 in a tight sweater in the Warner Bros. film "They Won't Forget," a scandal-drama released in 1937.

Miss Turner also is glad to have lost her nickname of the Sweater Girl. It disappeared when she went to the more dignified MGM. She doesn't wear sweaters now. ["Stop, Look--And Whistle," weekly news magazine profile of Turner, December 1939]