Online Etymology Dictionary

rite (n.): early 14c., from Latin ritus "religious observance or ceremony, custom, usage," perhaps from PIE root *re(i)- "to count, number" (source also of Greek arithmos "number," Old English rim "number;" see read (v.)). Rite of passage (1909) is translated from French rite de passage, coined by French anthropologist Arnold van Gennep (1873-1957).
ritual (adj.): 1560s, from Middle French ritual or directly from Latin ritualis "relating to (religious) rites," from ritus "rite" (see rite). Related: Ritually.
ritual (nj.): 1640s, from ritual (adj.).
ritualistic (adj.): 1844, from ritualist "one versed in or devoted to rituals" (1650s; see ritual) + -ic. Related: Ritualism (1838).
Ritz (n.): "high quality, superiority," 1910 (Ritzian, adj., is attested by 1908), in reference to the luxurious Ritz hotels in New York, London, Paris, etc., commemorating Swiss hotelier César Ritz (1850-1918). To put on the ritz "assume an air of superiority" is recorded from 1926. A verb ritz "to behave haughtily" is recorded from 1911.
ritzy: 1920, from ritz + -y (2). Related: Ritziness.
rival (n.): 1570s, from Latin rivalis "a rival, adversary in love; neighbor," originally, "of the same brook," from rivus "brook" (see rivulet). "One who is in pursuit of the same object as another." The sense evolution seems to be based on the competitiveness of neighbors: "one who uses the same stream," or "one on the opposite side of the stream" A secondary sense in Latin and sometimes in English was "associate, companion in duty," from the notion of "one having a common right or privilege with another." As an adjective 1580s from the noun.
rival (v.): c. 1600, from rival (n.). Related: Rivaled; rivaling.
rivalrous (adj.): 1812; see rivalry + -ous.
rivalry (n.): 1590s; from rival + -ry. Shakespeare has rivality ("Antony and Cleopatra"), but from the secondary sense of the root word and meaning "partnership, equality in rank."
rive (v.): "tear in pieces, strike asunder," c. 1200, from a Scandinavian source akin to Old Norse rifa "to tear apart" (compare Swedish rifva, Danish rive "scratch, tear"), from PIE root *rei- "to scratch, tear, cut" (see riparian).
riven (adj.): "split, cloven, rent," c. 1300, past participle adjective from rive "to tear, rend."
river (n.): early 13c., from Anglo-French rivere, Old French riviere "river, riverside, river bank" (12c.), from Vulgar Latin *riparia "riverbank, seashore, river" (source also of Spanish ribera, Italian riviera), noun use of fem. of Latin riparius "of a riverbank" (see riparian). Generalized sense of "a copious flow" of anything is from late 14c. The Old English word was ea "river," cognate with Gothic ahwa, Latin aqua (see aqua-). Romanic cognate words tend to retain the sense "river bank" as the main one, or else the secondary Latin sense "coast of the sea" (compare Riviera).

U.S. slang phrase up the river "in prison" (1891) is originally in reference to Sing Sing prison, which was literally "up the (Hudson) river" from New York City. Phrase down the river "done for, finished" perhaps echoes sense in sell down the river (1851), originally of troublesome slaves, to sell from the Upper South to the harsher cotton plantations of the Deep South.
riverine (adj.): 1849, from river + -ine (1). French form riverain is attested from 1858.
riverside (n.): c. 1400, from river + side (n.).
rivet (n.): c. 1400, from Old French rivet "nail, rivet," from Old French river "to clench, fix, fasten," possibly from Middle Dutch wriven "turn, grind," related to rive (v.). The English word may be directly from Middle Dutch.
rivet (v.): early 15c., from rivet (n.). Meaning "to command the attention" is from c. 1600. Related: Riveted; riveting.
riveter (n.): 1800, agent noun from rivet (v.).
riveting (adj.): "commanding attention," 1854, present participle adjective from rivet (v.). Related: Rivetingly.
Riviera (n.): Mediterranean seacoast around Genoa, 1630s, from Italian riviera, literally "bank, shore" (see river). In extended use, the coast from Marseilles to La Spezia, which became popular 19c. as a winter resort. Thence adopted (sometimes ironically) in reference to areas of other countries, as in American Riviera (Florida, 1887); English Riviera (Devonshire coast, 1882).
rivulet (n.): 1580s, from Italian rivoletto, diminutive of rivolo, itself a diminutive of rivo "brook," from Latin rivus "stream, brook," from PIE *reiwos, literally "that which flows," from root *reie- "to flow, run" (see Rhine). For ending, see -let.
RNA (n.): 1948, abbreviation of ribonucleic acid (see ribonucleic).
roach (n.1): shortened form of cockroach, 1837, on mistaken notion that it was a compound. In contemporary writing said to be from a polite desire to avoid the sexual connotation in the first syllable. Meaning "butt of a marijuana cigarette" is first recorded 1938, perhaps from resemblance to the insect, but perhaps a different word entirely.
roach (n.2): small freshwater fish, c. 1200, from Old French roche (13c.), of uncertain origin, perhaps from a Germanic source. Applied to similar-looking fish in North America.
road (n.): Old English rad "riding expedition, journey, hostile incursion," from Proto-Germanic *raido (source also of Old Frisian red "ride," Old Saxon reda, Middle Dutch rede, Old High German reita "foray, raid"), from PIE *reidh- "to ride" (see ride (v.)). Also related to raid (n.). In Middle English, "a riding, a journey;" sense of "open way for traveling between two places" is first recorded 1590s. Meaning "narrow stretch of sheltered water" is from early 14c. (as in Hampton Roads in Virginia).

Modern spelling established 18c. In 19c. U.S. use, often meaning "railroad." On the road "travelling" is from 1640s. Road test (n.) is from 1906; as a verb from 1937. Road hog is attested from 1886; road rage is from 1988. Road map is from 1786; road trip is by 1950, originally of baseball teams. Old English had radwerig "weary of travelling."
road kill (n.): also roadkill, animal killed by vehicular traffic, 1962; the figurative sense is from 1992.
road-runner (n.): "long-tailed crested desert cuckoo," 1847, American English, from road (n.) + runner. Earliest references give the Mexican Spanish name for it as correcamino and the English name might be a translation of that. The Warner Bros. cartoon character dates to 1948.
roadblock (n.): 1940, from road + block (n.).
roadhouse (n.): "inn by a roadside," 1857, later "place for refreshment and entertainment along a road" (1922), from road (n.) + house (n.).
roadie (n.): "laborer employed by pop groups while on tour," 1969, from road + -ie.
roadside (n.): 1744, from road (n.) + side (n.).
roadster (n.): "open two-seat automobile," 1908; earlier a light, horse-drawn carriage (1892); a horse for riding (1818); "a ship lying near the shore" (1744), from road (n.) + -ster.
roadwork (n.): also road-work, 1765, "work done in making and repairing roads;" 1903 as "exercise done on roads;" from road (n.) + work (n.).
roam (v.): c. 1300, romen, possibly from Old English *ramian "act of wandering about," which is probably related to aræman "arise, lift up." There are no certain cognate forms in other Germanic languages, but Barnhart points to Old Norse reimuðr "act of wandering about," reimast "to haunt." "Except in late puns, there is no evidence of connexion with the Romance words denoting pilgrims or pilgrimages to Rome ...." [OED], such as Spanish romero "a pilot-fish; a pilgrim;" Old French romier "travelling as a pilgrim; a pilgrim," from Medieval Latin romerius "a pilgrim" (originally to Rome). Related: Roamed; roamer; roaming.
roan (adj.): 1520s, from Middle French roan "reddish brown," perhaps from Spanish roano, from Old Spanish raudano, probably from a Germanic source (compare Gothic raudan, accusative of rauðs "red"). Chiefly of horses.
roar (v.): Old English rarian "roar, wail, lament, bellow, cry," probably of imitative origin (compare Middle Dutch reeren, German röhren "to roar;" Sanskrit ragati "barks;" Lithuanian reju "to scold;" Old Church Slavonic revo "I roar;" Latin raucus "hoarse"). Related: Roared; roaring.
roar (n.): late 14c., from roar (v.) and Old English gerar.
roaring (adj.): late 14c., present participle adjective from roar (v.). Used of periods of years characterized by noisy revelry, especially roaring twenties (1930); but also, in Britain, roaring fifties (1892). Roaring forties in reference to exceptional rough seas between latitudes 40 and 50 south, is attested from 1841.
roast (v.): late 13c., "to cook by dry heat," from Old French rostir "to roast, burn" (Modern French rôtir), from Frankish *hraustjan (cognate with Old High German rosten, German rösten, Middle Dutch roosten "to roast"), originally "cook on a grate or gridiron," related to Germanic words meaning "gridiron, grate;" such as German Rost, Middle Dutch roost.

Intransitive sense "be very hot, be exposed to great heat" is from c. 1300. The meaning "make fun of in an affectionate way" is from 1710. From the same source as roster. Related: Roasted; roasting. Roast beef first recorded 1630s (French rosbif is from English).
roast (n.): early 14c., "meat roasted or for roasting;" see roast (v.). Meaning "a roasting" is from 1580s. Sense of "an unmerciful bantering" is from 1740.
roaster (n.): mid-15c., agent noun from roast (v.). As a kind of oven, from 1799; as "article of food prepared for roasting," 1680s.
rob (v.): late 12c., from Old French rober "rob, steal, pillage, ransack, rape," from West Germanic *rauba "booty" (source also of Old High German roubon "to rob," roub "spoil, plunder;" Old English reafian, source of the reave in bereave), from Proto-Germanic *raubon "to rob," from PIE *reup-, *reub- "to snatch" (see rip (v.)).
Lord, hou schulde God approve þat þou robbe Petur, and gif þis robbere to Poule in þe name of Crist? [Wyclif, c. 1380]
To rob the cradle is attested from 1864 in reference to drafting young men in the American Civil War; by 1949 in reference to seductions or romantic relationships with younger persons. Related: Robbed; robbing.
Rob Roy (n.): Highland freebooter (1671-1734). His name means "Red Robert." As a type of cocktail made with Scotch whiskey, it is attested from 1960.
robber (n.): late 12c., from Anglo-French robbere, Old French robeor, agent noun from rober (see rob). Robber baron in the "corrupt, greedy financier" sense is attested from 1870s, from a comparison of Gilded Age capitalists to medieval European warlords.
It is the attempt of the more shrewd to take advantage of the less shrewd. It is the attempt of the strong to oppress the weak. It is the old robber baron in his castle descending, after men have planted their crops, and stealing them. [Henry Ward Beecher, sermon, "Truthfulness," 1871]

Regulation by combination means that the railroad managers are feudal lords and that you are their serfs. It means that every car load of grain or other produce of your fields and shops that passes over the New York Central shall pay heavy toll for right of transit to Vanderbilt, the robber baron of our modern feudalism, who dominates that way. [W.C. Flagg, testimony to Congress, 1874]
robbery (n.): c. 1200, from Old French roberie "robbery, theft," from rober "to rob" (see rob).
robe (n.): "long, loose outer garment," late 13c., from Old French robe "long, loose outer garment" (12c.), from a Germanic source (compare Old High German rouba "vestments"), from West Germanic *raubo "booty" (cognate with Old High German roub "robbery, breakage"), which also yielded rob (v.).

Presumably the notion is of garments taken from the enemy as spoils, and the Old French word had a secondary sense of "plunder, booty," while Germanic cognates had both senses; as in Old English reaf "plunder, booty, spoil; garment, armor, vestment." Meaning "dressing gown" is from 1854. Metonymic sense of "the legal profession" is attested from 1640s.
robe (v.): late 14c., from robe (n.). Related: Robed; robing.
Robert: masc. proper name, from Old North French form of Old High German Hrodberht "bright-fame, bright with glory," from hrod- "fame, glory," from Proto-Germanic *hrothi-, + -berht "bright" (see Albert). The name of William the Conqueror's rebellious oldest son. "It was introduced by Normans during the reign of Edward the Confessor and became very popular" ["Dictionary of English Surnames"].
robin (n.): common European songbird, 1540s, shortening of Robin Redbreast (mid-15c.), from masc. personal name Robin, also (in reference to the bird) in the diminutive form robinet. Redbreast alone for the bird is from early 15c., and the Robin might have been added for the alliteration. It ousted the native ruddock. In North America, the name was applied to the red-breasted thrush by 1703. Robin's egg as a shade of blue is attested from 1881.
Robin: masc. proper name, from Old French Robin, diminutive of Robert (q.v.). Robin Goodfellow "sportive elf of the English countryside," is first attested 1530s, popular 16-17c.; Robin Hood is at least from late 14c.