英语词源字典 - 在线词源网站

raster (n.)[raster 词源字典]: 1934 in electrical engineering, from German Raster "screen, frame," from Latin rastrum "rake," from rasum, from rodere "to scrape" (see raze). Related: Rasterization; rasterize. From Latin form rastellum comes French râteau "rake," formerly ratel, originally rastel.[raster etymology, raster origin, 英语词源]
Rastus: also 'Rastus, masc. proper name, short for Erastus. As a stereotypical name of an American slave or derogatory for "black man," 1881, probably from use in stories of Joel Chandler Harris.
rat (n.): late Old English ræt "rat," of uncertain origin. Similar words are found in Celtic (Gaelic radan), Romanic (Italian ratto, Spanish rata, French rat) and Germanic (Old Saxon ratta; Dutch rat; German Ratte, dialectal Ratz; Swedish råtta, Danish rotte) languages, but connection is uncertain and origin unknown. In all this it is very much like cat.

Perhaps from Vulgar Latin *rattus, but Weekley thinks this is of Germanic origin, "the animal having come from the East with the race-migrations" and the word passing thence to the Romanic languages. American Heritage and Tucker connect Old English ræt to Latin rodere and thus PIE *red- "to scrape, scratch, gnaw," source of rodent (q.v.). Klein says there is no such connection and suggests a possible cognate in Greek rhine "file, rasp." Weekley connects them with a question mark and Barnhart writes, "the relationship to each other of the Germanic, Romance, and Celtic words for rat is uncertain." OED says "probable" the rat word spread from Germanic to Romanic, but takes no position on ultimate origin.
RATS. Of these there are the following kinds: a black rat and a grey rat, a py-rat and a cu-rat. ["Dictionary of the Vulgar Tongue," Grose, 1788]
Middle English common form was ratton, from augmented Old French form raton. Sense of "one who abandons his associates" (1620s) is from belief that rats leave a ship about to sink or a house about to fall and led to meaning "traitor, informant" (1902; verb 1910). Interjection rats is American English, 1886. To smell a rat is 1540s; "to be put on the watch by suspicion as the cat by the scent of a rat; to suspect danger" [Johnson]. _____-rat, "person who frequents _____" (in earliest reference dock-rat) is from 1864.
rat (v.): 1812, "to desert one's party; 1864 as "to catch rats;" 1910 as "to peach on, inform on, behave dishonestly toward;" from rat (n.). Related: Ratted; ratting.
rat fink (n.): also ratfink, 1963, teen slang, see rat (n.) + fink (n.). Popularized by, and perhaps coined by, U.S. custom car builder Ed "Big Daddy" Roth (1932-2001), who made a hot-rod comic character of it, supposedly to lampoon Mickey Mouse.
rat-a-tat: 1680s, echoic, originally of a cooper hammering tubs.
rat-catcher (n.): 1590s, from rat (n.) + catcher.
rat-hole (n.): also rathole, 1812 in figurative sense of "nasty, messy place;" rat (n.) + hole (n.). As "bottomless hole" (especially one where money goes) from 1961.
rat-pack (n.): "juvenile gang," 1951, from rat (n.) + pack (n.). In reference to a Hollywood circle around Frank Sinatra, from 1958.
rat-poison (n.): "arsenic," 1799, from rat (n.) + poison (n.).
rat-race (n.): also rat race, 1934 in reference to aviation training, from rat (n.) + race (n.1). Rat-run is from 1870 in a literal sense.
A rat race is ... a simple game of "follow the leader" in fighter planes. The leader does everything he can think of -- Immelmanns, loops, snap rolls, and turns, always turns, tighter and tighter. ["Popular Science," May 1941]
Meaning "competitive struggle" is from 1945.
rat-tail (n.): also rat's-tail, used since 16c. of conditions or devices held to resemble a rat's long, hairless tail in some sense, including "lank lock of hair" (1810); "end of a rope" (1867); from rat (n.) + tail (n.1).
rat-trap (n.): late 15c., from rat (n.) + trap (n.).
ratable (adj.): also rateable, c. 1500, from rate (v.2) + -able.
ratafia (n.): liqueur flavored with kernels of cherries, apricots, etc., 1690s, from French ratafia (17c.), of unknown origin; perhaps ultimately from the same source as arrack.
ratatouille (n.): 1877, from French ratatouille (19c.), first element uncertain, second element evidently touiller "to stir up," ultimately from Latin tudes "hammer" [Gamillscheg].
ratbag (n.): also rat-bag, "unpleasant person," 1937, from rat (n.) + bag (n.).
ratchet (v.): 1852, from ratchet (n.). Transferred sense attested by 1977. Related: Ratcheted; ratcheting.
ratchet (n.): 1650s, rochet, from French rochet "bobbin, spindle," from Italian rocchetto "spool, ratchet," diminutive of rocca "distaff," possibly from a Germanic source (compare Old High German rocko "distaff," Old Norse rokkr), from Proto-Germanic *rukka-, from PIE root *ruk- "fabric, spun yarn." Compare rocket (n.2). Current spelling in English dates from 1721, influenced by synonymous ratch, which perhaps is borrowed from German Rätsche "ratchet."
rate (n.): "estimated value or worth," early 15c., from Old French rate "price, value" and directly from Medieval Latin rata (pars) "fixed (amount)," from Latin rata "fixed, settled," fem. past participle of reri "to reckon, think" (see reason (n.)). Meaning "degree of speed" (properly ratio between distance and time) is attested from 1650s. Currency exchange sense first recorded 1727. First-rate, second-rate, etc. are 1640s, from British Navy division of ships into six classes based on size and strength. Phrase at any rate originally (1610s) meant "at any cost;" weakened sense of "at least" is attested by 1760.