1935, from name of hard-working Soviet coal miner Aleksei Grigorevich Stakhanov (1906-1977), in reference to an efficiency system in which workers increase their piecework production and are rewarded with bonuses and privileges. Soviet authorities publicized his prodigious output as part of a campaign to increase productivity.
"state policeman," 1974, from truckers' slang, in reference to the wide-brim style of hat worn by state troopers (the hats so called by 1969). Ultimately the reference is to the popular illustrated character of that name, a bear dressed in forest ranger gear (including a hat like those later worn by state troopers). He was introduced in 1944 by the U.S. Forest Service and the Wartime Advertising Council in a campaign to lower the number of forest fires in the West.
1864, named for its designer, U.S. inventor Richard Jordan Gatling (1818-1903); patented by 1862 but not used in American Civil War until the Petersburg campaign of June 1864 as an independent initiative by U.S. Gen. Ben Butler.
For the first time in this war, the Gatling gun was used by Butler in repelling one of Beauregard's midnight attacks. Dispatches state that it was very destructive, and rebel prisoners were very curious to know whether it was loaded all night and fired all day. [Scientific American, June 18, 1864]
fem. proper name, Danish shortened form of Katherine. Rare before 1928; a top-10 name for girls born in the U.S. 1951-1968.
The modern pejorative use in reference to a person regarded as ignorant, meddlesome, entitled, racist, or generally negative, is attested by 2005, originally often with reference to meanness or stupidity, and exploded in popularity 2018, with more emphasis on the racism and privilege. Its use as rhetorical shorthand probably was encouraged, if not inspired by, the 2004 movie "Mean Girls" (screenplay by Tina Fey) and by U.S. comedian Dane Cook's 2005 stand-up act, both of which produced memes and Twitter references. Claims that it originated in African-American circles are unsupported.
Beth Harpaz's 2001 book "Girls in the Van," about Hillary Clinton's U.S. Senate campaign, reports that Clinton's assistants Karen Dunn and Karen Finney were known as The Karens. Finney went on to a career as a commentator, and some of the earliest abstract uses of Karen in the late 2000s are as the personification of a liberal do-gooder.