A- (3) prefix meaning "not," from Gk a-, an- "not," from pie base *ne "not" (see un-)

rotor --- 1873, irregular shortening of rotator, originally in mathematics. Mechanical sense is attested from 1903; specifically of helicopters from 1930. Rototiller (with tiller) is a proprietary name in U.S., attested from 1923.

rotten --- c.1225, from O.N. rotinn "decayed," pp. of verb related to rotna "to decay," from P.Gmc. stem *rut- (see rot). Sense of "corrupt" is from c.1380; weakened sense of "bad" first recorded 1881. Rotter "objectionable person" is recorded from 1894. Rotten apple is from a saying traced back to at least 1528: For one rotten apple lytell and lytell putrifieth an whole heape.

Rottweiler --- 1907, from Rottweil, town in Württemberg, southern Germany.

rotund --- 1705, from L. rotundus "round, circular, like a wheel," from rota "wheel" (see rotary). Meaning "full-toned style of oratory" (1830) is after Horace's ore rotundo in "Poetics."

rotunda --- round building, 1687, from It. rotonda, especially the Pantheon, from L. rotunda, fem. of rotundus "round" (see rotund). Meaning "circular hall or room within a building" is from 1780.

roué --- 1800, from Fr. roué "dissipated man, rake," originally pp. of O.Fr. rouer "to break on the wheel," from L. rotare "roll;" said to have been first applied in Fr. c.1720 to dissolute friends of the Duke of Orleans (regent of France 1715-23), to suggest the punishment they deserved.

rouge --- 1753, in cosmetic sense, from Fr. rouge "red coloring matter," from adj. "red," from L. rubeus, related to ruber "red." Replaced native paint in this sense. The verb is attested from 1777.

rough (adj.) --- O.E. ruh "rough, untrimmed, uncultivated," from W.Gmc. *rukhwaz "shaggy, hairy, rough" (cf. M.Du. ruuch, Du. ruig, O.H.G. ruher, Ger. rauh), from P.Gmc. *rukhaz. The original -gh- sound was guttural, as in Scottish loch. Sense of "approximate" is first recorded 1607. The noun meaning "broken ground" is from 1480 (phrase in the rough first recorded 1823); specific sense in golf is from 1901. Noun meaning "a rowdy" is first attested 1837. Rough draft is from 1699. Rough-and-ready is from 1810, originally military; rough-and-tumble (1810) is from the prize ring; .

rough (v.) --- 1483, from rough (adj.), q.v. Phrase rough it (1768) is originally nautical; to rough (someone) up is from 1868. The U.S. football penalty roughing was originally a term from boxing (1866).

roughage --- 1883, "rough grass or weeds," from rough. Meaning "coarse, bulky food" first recorded 1927.

rough-house --- 1887, as a noun, "uproar, disturbance," from rough (adj.) + house. The verb is first attested c.1897.

rough-neck --- 1836, "rugged individual," from rough (adj.) + neck. Original context is the Texas frontier, later adpoted to labor organization toughs. Specific sense of "oil rig worker" is recorded from 1917.

rough-rider --- 1733, "horse-breaker," from rough (adj. or adv.) + rider. In specific military use, a non-commissioned officer in cavalry regiments from 1802; sense of "one who can ride an unbroken horse" is from 1828; meaning "irregular cavalryman" is attested from 1884.

rough-shod --- 1688, from rough (adj.) + shod, past tense of shoe (v.) "to shoe a horse." originally from horses shod with the nails projecting from the shoe, to prevent slipping.

roulette --- 1734, "small wheel," from Fr. roulette "gambling game played with a revolving wheel," lit. "small wheel," from O.Fr. roelete "little wheel," on model of L.L. rotella, dim. of L. rota "wheel." The game of chance so-called from 1745.

round (adj., adv.) --- c.1290, from Anglo-Fr. rounde, O.Fr. roont, probably originally *redond, from V.L. *retundus (cf. Prov. redon, Sp. redondo, O.It. ritondo), from L. rotundus "like a wheel, circular, round," related to rota "wheel" (see rotary). The O.Fr. word is the source of M.Du. ront (Du. rond), M.H.G. runt (Ger. rund) and similar Gmc. words. In many uses it is an aphetic form of around. First record of round trip is from 1860. Round number is 1646, from earlier sense of "full, complete" (1340, sense of symmetry extended to that of completeness); roundhouse (1589) is from Du. rondhuis "guardhouse." King Arthur's Round Table is attested from c.1300, from O.Fr. table ronde (1155, in Wace's Roman de Brut). Roundhead "adherent of Parliamentary party in the English Civil War" (1641) is from their custom of wearing the hair close-cropped, in contrast to the flowing curls of the cavaliers. Round heels attested from 1926, in ref. to incompetent boxers, 1927 in ref. to loose women, in either case implying an inability to avoid ending up flat on one's back.

round (n.) --- c.1330, "a spherical body," from round (adj.) (cf. Du. rond, Dan., Swed. rund, Ger. runde, all n. from adj.). Meaning "large round piece of beef" is recorded from 1660. Theatrical sense (in phrase in the round) is recorded from 1944. Sense of "circuit performed by a sentinel" is from 1598; that of "recurring course of time" is from 1710. Meaning "song sung by two or more, beginning at different times" is from 1530. Golfing sense attested from 1775. Meaning "quantity of liquor served to a company at one time" is from 1633; that of "single bout in a fight or boxing match" is from 1812; "single discharge of a firearm" is from 1725. Sense of "recurring session of meetings or negotiations" is from 1964.

round (v.) --- c.1375, "to make round," from round (adj.). Meaning "to approximate a number" is from 1934. Round up "to collect in a mass" is from 1615; specifically of livestock from 1847; round-up (n.) "cattle drive" is from 1873;

round robin --- petition or complaint signed in a circle to disguise the order in which names were affixed and prevent ringleaders from being identified, 1730, originally in ref. to sailors and frequently identified as a nautical term. As a kind of tournament in which each player plays the others, it is recorded from 1895.

roundabout (adv.) --- by a circuitous route, 1870, from round (adv.) + about. Noun sense of "traffic circle" is attested from 1927.

roundelay --- 1573, from M.Fr. rondelet, dim. of rondel "short poem with a refrain," lit. "small circle," from O.Fr. rondel, dim. of rond "circle, sphere," originally an adj. from roont (see round). Spelling developed by association with lay (n.) "poem to be sung."

rounder --- 1624, "a sentinel," from round (n.) on notion of "one who makes the rounds." Sense of "chronic drunkard or criminal" is from 1854, on notion of one who is habitually in and out of jails or bars.

rouse --- c.1460, probably from Anglo-Fr., or O.Fr., originally used of hawks shaking the feathers of the body, but like many hawking terms of obscure origin. Meaning "to stir up, provoke to activity" is from 1586; that of "awaken" is first recorded 1590.

roust --- 1658, probably an alteration of rouse. Roustabout "deck hand, wharf worker" is from 1868, perhaps from roust + about, but another theory connects it to Brit. dial. rousing "rough, shaggy," a word associated perhaps with rooster.

rout --- 1598, "disorderly retreat," from M.Fr. route "disorderly flight of troops," lit. "a breaking off, rupture," from V.L. rupta "a dispersed group," lit. "a broken group," from L. rupta, fem. pp. of rumpere "to break" (see rupture). The verb is from 1600.

route --- c.1225, from O.Fr. rute "road, way, path," from L. rupta (via) "(a road) opened by force," from rupta, fem. pp. of rumpere "to break" (see rupture). Sense of "fixed or regular course for carrying things" (cf. mail route) is 1792, an extension of the meaning "customary path of animals" (1410).

router --- cutter that removes wood from a groove, 1818, from rout "poke about, rummage" (1547), originally of swine digging with the snout; a variant of root (v.1).

routine (n.) --- 1676, from Fr. routine "usual course of action, beaten path" from route "way, path, course" (see route) + subst. suffix -ine. Theatrical sense is from 1926. The adj. is attested from 1817, from the noun.

rove --- to wander with no fixed destination, 1536, possibly a Midlands dialectal variant of northern Eng. and Scottish rave "to wander, stray," from M.E. raven, probably from O.N. rafa "to wander, rove." Infl. by rover (q.v.). Earliest sense was "to shoot arrows at a mark selected at pleasure or at random" (1474).

rover --- 1390, "sea-robber, pirate," from M.Du. rover "robber, predator, plunderer," especially in zeerovere "pirate," lit. "sea-robber," from roven "to rob," from M.Du. root "spoil, plunder," related to O.E. reaf "spoil, plunder," reafian "to reave" (see reft).

row (1) --- line of people or things, O.E. ræw "a row, line," from P.Gmc. *rai(h)waz (cf. M.Du. rie, Du. rij "row;" O.H.G. rihan "to thread," riga "line;" Ger. Reihe "row, line, series;" O.N. rega "string"), possibly from PIE base *rei- "to scratch, tear, cut" (cf. Skt. rikhati "scratches," rekha "line"). Meaning "a number of houses in a line" is attested from 1450, originally chiefly Scottish and northern English. Row-house is first recorded 1936, Amer.Eng. Phrase a hard row to hoe first attested 1835, in writing of Davy Crockett.

row (2) --- propel with oars, O.E. rowan (class VII strong verb; past tense reow, pp. rowen), from P.Gmc. *ro- (cf. O.N. roa, Du. roeien, W.Fris. roeije, M.H.G. rüejen), from PIE base *ere- "to row" (cf. Skt. aritrah "oar;" Gk. eressein "to row," eretmon "oar," trieres "trireme;" L. remus "oar;" Lith. iriu "to row," irklas "oar;" O.Ir. rome "oar," O.E. roðor "rudder"). First record of rowboat is from 1538 (cf. Du. roeiboot).

row (3) --- noisy commotion, 1746, Cambridge University slang, of uncertain origin, perhaps related to rousel "drinking bout" (1602), a shortened form of carousal. Klein suggests a back-formation from rouse (n.), mistaken as a plural (cf. pea from pease).

rowan --- mountain ash, 1804, from rowan-tree, rountree (1548), northern English and Scottish, from a Scandinavian source (cf. O.N. reynir, Swed. Ronn "the rowan"), ultimately from the root of red, in reference to the berries. The rowan "was the tree most often credited with protective magical powers against all effects of witchcraft, not merely in Celtic areas but throughout Britain." ["Oxford Dictionary of English Folklore"]

rowdy (n.) --- a rough, quarrelsome person, 1808, Amer.Eng., originally "lawless backwoodsman," probably from row (3) (q.v.). The adjective is first recorded 1819.

rowel --- pointed wheel on a spur, 1344, from O.Fr. roelle "small wheel" (see roulette).

Roxanne --- fem. proper name, from Fr., from L. Roxane, from Gk. Rhoxane, of Pers. origin (cf. Avestan raoxšna- "shining, bright").

Roxy --- cinema chain built by U.S. radio and film entrepreneur Samuel Lionel Rothafel (1882-1936).

royal --- c.1250, from O.Fr. roial, from L. regalis, from rex (gen. regis) "king" (see rex). Battle royal (1672) preserves the Fr. custom of putting the adj. after the noun (cf. attorney general); the sense of the adj. here is "on a grand scale." As a modifier meaning "thorough, total" royal is attested in Eng. from 1940s. Royalist first recorded 1643. The Royal Oak was a tree in Boscobel in Shropshire in which Charles II hid himself during flight after the Battle of Worcester in 1651. Sprigs of oak were worn to commemorate his restoration in 1660.

royalty --- 1398," office or position of a sovereign," from O.Fr. roialte, from V.L. *regalitatem (nom. *regalitas), from L. regalis (see royal). Sense of "prerogatives or rights granted by a sovereign to an individual or corporation" is from 1483. From that evolved more general senses, such as "payment to a landowner for use of a mine" (1839), and ultimately "payment to an author, composer, etc." for sale or use of his or her work (1857).

rub (v.) --- 1377, perhaps related to E.Fris. rubben "to scratch, rub," and Low Ger. rubbeling "rough, uneven," or similar words in Scandinavian (cf. Dan. rubbe "to rub, scrub," Norw. rubba), of uncertain origin. Hamlet's there's the rub (1602) preserves a noun sense of "obstacle, inequality on ground" first recorded 1586 and common in 17c. To rub (someone) the wrong way is from 1883. To rub noses in greeting as a sign of friendship (attested from 1822) formerly was common among Eskimos, Maoris, and some other Pacific Islanders. Rub out "obliterate" is from 1567; underworld slang sense of "kill" is recorded from 1848, Amer.Eng. Rub off "have an influence on" is recorded from 1959.

rub-a-dub --- 1787, echoic of the sound of a drum.

rubaiyat --- quatrains (in Pers. poetry), 1859, pl. of rubai, from Arabic rubaiyah, from rubaiy "composed of four elements."

rubber --- thing that rubs, 1536, from rub (v.). The meaning "elastic substance from tropical plants" (short for India rubber) first recorded 1788, introduced to Europe 1744 by Charles Marie de la Condamine, so called because it was originally used as an eraser.

rubbish --- c.1400, from Anglo-Fr. rubouses (1392), of unknown origin. Apparently somehow related to rubble. The verb sense of "disparage, criticize harshly" is first attested 1953 in Australian and New Zealand slang.

rubble --- c.1400, from Anglo-Norm. *robel "bits of broken stone," probably related to rubbish, but also possibly from O.Fr. robe (see rob).

rube --- 1896, reub, from shortened form of masc. proper name Reuben (q.v.), which is attested from 1804 as a conventional type of name for a country man.

Rube Goldberg --- 1940, from the U.S. cartoonist Reuben Lucius Goldberg (1883-1970) who devised fantastically complex gadgetry to accomplish simple tasks. His British counterpart was Heath Robinson (1872-1944).

rubella --- German measles, 1883, from Mod.L., lit. "rash," from L., neut. pl. of rubellus "reddish," dim. of ruber "red" (see red).

Rubenesque --- of a woman's body, "rounded and plump," 1913, of the type characteristic of the paintings of Flem. painter Sir Peter Paul Rubens (1577-1640).

Rubicon --- in phrase "to cross (or "pass") the Rubicon "take a decisive step," 1626, in ref. to small stream to the Adriatic on the coast of northern Italy, which in ancient times formed part of the southern boundary of Cisalpine Gaul; crossed by Caesar Jan. 10, 49 B.C.E., when he left his province to attack Pompey. The name is from L. rubicundus "ruddy," in ref. to the color of the soil on its banks.

Rubik's Cube --- 1980, named for teacher Ernö Rubik, who patented it in Hungary in 1975.

ruble --- unit of Rus. monetary system, 1554, via Fr., from Rus. rubl', perhaps from rubiti "to chop, cut," so called because the original metallic currency of Russia (14c.) consisted of silver bars, from which the necessary amount was cut off.

rubric --- c.1375, "directions in religious services" (often in red writing), from O.Fr. rubrique, from L. rubrica "red ochre, red coloring matter," from ruber, from PIE base *rudhro- (see red).

ruby --- c.1300, from O.Fr. rubi, from M.L. rubinus lapis "red stone" (cf. It. rubino), from L. rubeus "red," related to ruber (see red). Mod.Fr. rubis is prop. the plural of rubi, mistaken for sing.

rucksack --- 1866, from Ger. Rucksack, from Alpine dialect Rück "the back" (from Ger. Rücken) + Sack "sack."

ruckus --- 1890, possibly a blend of ruction "disturbance" (1825) and rumpus (q.v.).

rudder --- O.E. roðor "paddle, oar," from P.Gmc. *rothru- (cf. O.Fris. roder, M.L.G. roder, M.Du. roeder, Du. roer, O.H.G. ruodar, Ger. Ruder "oar"), from *ro- "steer" (see row (2)) + suffix -þra, used to form neutral names of tools. Meaning "broad, flat piece of wood attached to the stern of a boat and used for steering" is from c.1303. Spelling with -d- for -th- first recorded 1440.

ruddy --- O.E. rudig, probably from rudu "redness," related to read "red" (see red). As a British slang euphemism for bloody (q.v.), first recorded 1914.

rude --- c.1280, "coarse, rough" (of surfaces), from L. rudis "rough, crude, unlearned," perhaps related to rudus "rubble." Sense of "ill-mannered" is from c.1386. Rudesby "insolent, unmannerly fellow" is from 1566. Rude boy (also rudie, for short) in Jamaican slang is attested from 1967. Fig. phrase rude awakening is attested from 1895.

rudiment --- 1548, from M.Fr. (16c.), from L. rudimentum "early training, first experience, beginning, first principle," from rudis "unlearned, untrained" (see rude). Rudimentary is from 1839.

Rudolph --- masc. proper name, from Ger. Rudolf, from O.H.G. Hrodulf, lit. "fame-wolf," from hruod- "fame, glory" + wolf.

Rudra --- storm god in Vedic mythology, from Skt. Rudrah, lit. "the howler, roarer," from stem of rudati "weeps, laments, bewails," cognate with L. rudere "to roar, bellow," Lith. rauda "wail, lamentation," O.E. reotan "to wail, lament."

rue (n.) --- perennial evergreen shrub, 1382, from O.Fr. rue, earlier rude, from L. ruta "rue," probably from Gk. rhyte, of uncertain etymology, originally a Peloponnesian word. The bitter taste of its leaves led to many punning allusions to the noun form of rue (v.).

rue (v.) --- feel regret, O.E. hreowan "make sorry, grieve" (class II strong verb; past tense hreaw, pp. hrowen), from P.Gmc. *khrewanan (cf. O.Fris. riowa, M.Du. rouwen, O.D. hrewan, Ger. rewen); in part, blended with O.E. weak v. hreowian "feel pain or sorrow," and perhaps influenced by O.N. hryggja "make sad," both from P.Gmc. *khruwjanan, from the same root. The noun meaning "sorrow, repentance" is from O.E. hreow, from the verb.

ruff (n.) --- kind of large collar, stiffly starched, worn in 17c., 1523, originally in ref. to sleeves (of collars, from 1555), probably a shortened form of ruffle. Card-playing sense is a separate word, from a former game of that name (1589), from M.Fr. roffle, earlier romfle (1414), from It. ronfa, perhaps a corruption of trionfo "triumph" (from Fr., cf. trump). The game was in vogue c.1590-1630.

ruffian --- 1531, from M.Fr. rufian "a pimp," from It. ruffiano "a pander, pimp," of uncertain origin, perhaps from a Gmc. source related to rough (q.v.), but Du. roffiaan, Ger. Ruffian are said to be from French. Eng. meaning may have been influenced by similarity of sound to rough. The Romanic words (e.g. M.L. ruffianus, Prov. rufian, Catalan rufia, Sp. rufian) preserve the sense of "protector or owner of whores." For sense evolution in Eng., cf. bully.

ruffle (v.) --- c.1300, "to disturb the smoothness of," perhaps from O.N. hrufla "to scratch," or Low Ger. ruffelen "to wrinkle, curl," both of unknown origin. Meaning "disarrange" (hair or feathers) first recorded 1490; sense of "annoy, distract" is from 1658. The noun meaning "ornamental frill" is from 1707.

rufous --- reddish-brown, 1782, from L. rufus "red, reddish, red-haired," from Osco-Umbrian cognate of L. ruber "red" (see red).

Rufus --- masc. proper name, lit. "red-haired," from L. rufus (see rufous).

rug --- 1551, "coarse fabric," of Scand. origin, cf. Norw. dial. rugga "coarse coverlet," from O.N. rogg "shaggy tuft," probably related to rag and perhaps also rough. Sense evolved to "coverlet, wrap" (1591), then "mat for the floor" (1808). Meaning "toupee" is theater slang from 1940. Cut a rug "dance" is slang first attested 1942. To sweep (something) under the rug in the fig. sense is from 1961. Rug-rat "baby, child" is from 1968.

rugby --- 1864, after Rugby, public school where the game was played, from city of Rugby in Warwickshire, central England. The place name is Rocheberie (1086) "fortified place of a man called *Hroca;" with second element from O.E. burh (dat. byrig), replaced by 13c. with O.N. -by "village" due to the infl. of Dan. settlers. Otherwise it might be *Rockbury today. First element perhaps rather O.E. hroc "rook." Rugby Union formed 1871. Slang rugger for "rugby player" is from 1893.

rugged --- c.1330, "rough, shaggy, careworn" (originally of animals), from O.N. rogg "shaggy tuft" (see rug). "The precise relationship to ragged is not quite clear, but the stem is no doubt ultimately the same" [OED]. Meaning "strong, robust" is Amer.Eng., 1848.

ruin (n.) --- c.1375, "act of giving way and falling down," from O.Fr. ruine, from L. ruina "a collapse" (cf. Sp. ruina, It. rovina), related to ruere "to rush, fall violently, collapse," of unknown origin. Meaning "complete destruction of anything" is from 1673. The verb is first recorded 1581, from the noun; financial sense is attested from 1660. Ruins "remains of a decayed building or town" is from 1454.

rule (n.) --- c.1225, "principle or maxim governing conduct," from O.Fr. riule, from V.L. *regula, from L. regula "straight stick, bar, ruler, pattern," related to regere "to rule, straighten, guide" (see right). Replaced O.E. wealdan. Meaning "regulation governing play of a game, etc." is from 1697. Phrase rule of thumb first attested 1692. Rule of law "supremacy of impartial and well-defined laws to any individual's power" is from 1883. Meaning "Strip used for making straight lines" is recorded from 1340. Typography sense is attested from 1683.

rule (v.) --- c.1225, "to control, guide, direct," from O.Fr. riuler, from L. regulare. Legal sense is recorded from 1425 (ruling "judicial decision" is from 1560). Ruler "one who rules" is recorded from c.1375; meaning "strip used for making straight lines" is c.1400 (see rule (n.)). "Rule Brittania," patriotic song, is from 1740.

rum (adj.) --- excellent, 1567, from rome "fine" (1567), said to be from Romany rom "male, husband" (see Romany). A very common 16c. cant word, by 1774 it had come to mean "odd, strange, bad, spurious," perhaps because it had been so often used approvingly by rogues in ref. to one another. This was the main sense after c.1800.

rum (n.) --- liquor from sugar cane or molasses, 1654, originally rumbullion (1651), rombostion (1652), of uncertain origin, perhaps from rum (adj.).

rumba (n.) --- 1922, from Cuban Sp., originally "spree, carousal," derived from Sp. rumbo "spree, party," earlier "ostentation, pomp, leadership," perhaps originally "the course of a ship," from rombo "rhombus," in reference to the compass, which is marked with a rhombus. The verb is recorded from 1944.

rumble (v.) --- c.1384, probably related to M.Du. rommelen "to rumble," M.H.G. rummeln, O.N. rymja "to shout, roar," all of imitative origin. The noun is attested from c.1386. Slang noun meaning "gang fight" is from 1946. Meaning "backmost part of a carriage" is from 1808 (earlier rumbler, 1801), probably from the effect of sitting over the wheels; hence rumble seat (1912).

ruminant (n.) --- 1661, from L. ruminantem (nom. ruminans), prp. of ruminare "to chew the cud" (see ruminate).

ruminate --- 1533, "to turn over in the mind," also "to chew cud" (1547), from L. ruminatus, pp. of ruminare "to chew the cud, turn over in the mind," from rumen (gen. ruminis) "gullet," of uncertain origin.

rummage --- 1526, "act of arranging cargo in a ship," aphetic of M.Fr. arrumage "arrangement of cargo," from arrumer "to stow goods in the hold of a ship," from a- "to" + rumer, probably from Gmc. (cf. O.N. rum "compartment in a ship," O.H.G. rum "space," O.E. rum, see room). Meaning "to search (the hold of a ship) thoroughly" first recorded 1628. Rummage sale (1858) originally was a sale at docks of unclaimed goods.

rummy --- card game, 1910, rhummy, of unknown origin. Gin rummy is first attested 1941. Meaning "drunkard" is 1851, from rum. Meaning "opponent of temperance" in U.S. politics is from 1860.

rumor --- c.1374, from O.Fr. rumour "widespread noise or report" (Fr. rumeur), from L. rumorem (nom. rumor) "noise, clamor, common talk, rumor," related to ravus "hoarse." The verb is recorded from 1858 in the sense "spread a rumor." Rumor mill is from 1973.

rump --- hind-quarters, buttocks of an animal, c.1440, from a Scand. source (cf. Dan., Norw. rumpe, Swed. rumpa), cognate with M.Du. romp, Ger. Rumpf "trunk, torso." Sense of "small remnant" derives from "tail" and is first recorded 1649 in ref. to the Eng. Rump Parliament (December 1648-April 1653).

rumple (v.) --- 1603, possibly a variant of rimple "to wrinkle" (14c.), from O.E. hrympel; possibly influenced by M.Du. rumpelen.