Online Etymology Dictionary

rampart (n.): "earthen elevation around a place for fortification," sometimes also including parapets, 1580s, from Middle French rempart, rampart, from remparer "to fortify," from re- "again" (see re-) + emparer "fortify, take possession of," from Old Provençal amparer, from Vulgar Latin *anteparare "prepare," properly "to make preparations beforehand," from Latin ante- "before" (see ante) + parare "prepare" (see pare). With excrescent -t in French, perhaps by influence of boulevart (see boulevard).
ramrod (n.): 1757, literally "a rod used in ramming" (the charge of a gun), from ram (v.) + rod. Used figuratively for straightness or stiffness from 1939, also figuratively for formality, primness (ramroddy is in Century Dictionary, 1902). The verb is 1948, from the noun. Related: Ramrodded; ramrodding.
ramshackle (adj.): 1809, back-formation from ramshackled, earlier ranshackled (1670s), alteration of ransackled, past participle of ransackle (see ransack). The word seems to have been Scottish.
Reading over this note to an American gentleman, he seemed to take alarm, lest the word ramshackle should be palmed on his country. I take it home willingly, as a Scotticism, and one well applied, as may be afterwards shown. [Robert Gourlay, "General Introduction to a Statistical Account of Upper Canada," London, 1822]
Jamieson's "Etymological Dictionary of the Scottish Language" (1825) has it as a noun meaning "thoughtless, ignorant fellow."
ramus (n.): "a branch" (anatomical), 1803, from Latin ramus "a branch, bough, twig," related to radix "root;" see radish.
ran: past tense of run (v.), Old English ran.
ranch (n.): 1808, "country house," from American Spanish rancho "small farm, group of farm huts," from Spanish rancho "mess-room," originally, "group of people who eat together," from ranchear "to lodge or station," from Old French ranger "install in position," from rang "row, line" (see rank (n.)).

Sense of "large stock-farm and herding establishment" is from 1831. Of houses, "single-story, split-level" (adj.) from 1950; as a noun from 1960. Ranch-house attested from 1862.
ranch (v.): 1866, from ranch (n.). Related: Ranched; ranching.
rancher (n.): 1836, "owner of a ranch;" see ranch (n.). Meaning "modern single-story house" attested from 1964.
ranchero (n.): "one employed on a ranch," 1826, from American Spanish ranchero, from rancho (see ranch (n.)).
rancid (adj.): 1640s, from Latin rancidus "rank, stinking, offensive" (also source of Italian rancido, Spanish rancio), from rancere "be spoiled or rotten," of unknown origin. German ranzig is from French rancide. Related: Rancidness.
rancor (n.): c. 1200, from Old French rancor "bitterness, resentment; grief, affliction," from Late Latin rancorem (nominative rancor) "rancidness, a stinking smell" (Palladius); "grudge, bitterness" (Hieronymus and in Late Latin), from Latin rancere "to stink" (see rancid).
rancorous (adj.): 1580s, from rancor + -ous. Related: Rancorously; rancorousness.
rancour (n.): chiefly British English spelling of rancor; for ending see -or. Related: Rancourous.
rand (n.): "rocky ridge overlooking a river valley," 1839, South African English, from Afrikaans, from Dutch rand "edge, margin," cognate with Old English rand "brink, bank." As a unit of currency, adopted by the Republic of South Africa in 1961 (see Krugerrand). Johnson's dictionary has rand "Border; seam: as the rand of a woman's shoe."
Randal: masc. proper name, shortened from Old English Randwulf, from rand "shield" (see rand) + wulf "wolf" (see wolf (n.)). Compare Randolph.
Randolph: masc. proper name, from Old Norse Rannulfr "shield-wolf" and Frankish *Rannulf "raven-wolf," both brought to England by the Normans.
random (adj.): "having no definite aim or purpose," 1650s, from at random (1560s), "at great speed" (thus, "carelessly, haphazardly"), alteration of Middle English noun randon "impetuosity, speed" (c. 1300), from Old French randon "rush, disorder, force, impetuosity," from randir "to run fast," from Frankish *rant "a running" or some other Germanic source, from Proto-Germanic *randa (source also of Old High German rennen "to run," Old English rinnan "to flow, to run;" see run (v.)).

In 1980s U.S. college student slang it began to acquire a sense of "inferior, undesirable." (A 1980 William Safire column describes it as a college slang noun meaning "person who does not belong on our dormitory floor.") Random access in reference to computer memory is recorded from 1953. Related: Randomly; randomness.
randomize (v.): 1926, from random (adj.) + -ize. Related: Randomized; randomizing.
randy (adj.): 1690s, Scottish, "aggressive, boisterous," probably from rand "to rave," an obsolete variant of rant (v.). In the original sense especially of beggars, "and probably implying vagrant habits as well as rude behavior" [OED]. Sense of "lewd, lustful" first recorded 1847. Related: Randiness.
rang (v.): past tense of ring (v.1). Middle English, by analogy of sang/sing, etc.
range (n.): c. 1200, "row or line of persons" (especially hunters or soldiers), from Old French range "range, rank" (see range (v.)). General sense of "line, row" is from early 14c.; meaning "row of mountains" is from 1705.

Meaning "scope, extent" first recorded late 15c.; that of "area over which animals seek food" is from 1620s, from the verb. Specific U.S. sense of "series of townships six miles in width" is from 1785. Sense of "distance a gun can send a bullet" is recorded from 1590s; meaning "place used for shooting practice" is from 1862. The cooking appliance so called since mid-15c., for unknown reasons. Originally a stove built into a fireplace with openings on top for multiple operations. Range-finder attested from 1872.
range (v.): c. 1200, rengen, "move over a large area, roam with the purpose of searching or hunting," from Old French ranger, earlier rengier "to place in a row, arrange; get into line," from reng "row, line," from a Germanic source (see rank (n.)). Sense of "to arrange in rows" is recorded from c. 1300; intransitive sense of "exist in a row or rows" is from c. 1600. Related: Ranged; ranging.
ranger (n.): late 14c., "gamekeeper," agent noun from range (v.)). Attested from 1660s in sense of "man (often mounted) who polices an area." The elite U.S. combat unit is attested from 1942 (organized 1941).
rangy (adj.): "having a long, slender form" (as an animal suited to ranging), 1845, from range (v.) + -y (2). Also "adapted for ranging" (1868). Of landscapes, "hilly," 1862, Australian English. Related: Ranginess.
As a rule, we hold that the Jersey should be "growthy," deep-flanked, and loose-jointed, and should have, generally, the characteristics which farmers know as "rangy." ["American Agriculturalist," November 1876]
rank (n.): early 14c., "row, line series;" c. 1400, a row of an army, from Old French renc, ranc "row, line" (Modern French rang), from Frankish *hring or some other Germanic source (compare Old High German hring "circle, ring"), from Proto-Germanic *hringaz "circle, ring, something curved" (see ring (n.1)).

Meaning "a social division, class of persons" is from early 15c. Meaning "high station in society" is from early 15c. Meaning "a relative position" is from c. 1600.
rank (adj.): Old English ranc "proud, overbearing, showy," from Proto-Germanic *rankaz (source also of Danish rank "right, upright," German rank "slender," Old Norse rakkr "straight, erect"), perhaps from PIE *reg- "to stretch, straighten" (see right (adj.)). In reference to plant growth, "vigorous, luxuriant, abundant, copious" it is recorded from c. 1300. Related: Rankly; rankness.

Sense evolved in Middle English to "large and coarse" (c. 1300), then, via notion of "excessive and unpleasant," to "corrupt, loathsome, foul" (mid-14c.), perhaps from influence of Middle French rance "rancid." In 17c. also "lewd, lustful."

Much used 16c. as a pejorative intensive (as in rank folly). This is possibly the source of the verb meaning "to reveal another's guilt" (1929, underworld slang), and that of "to harass, abuse," 1934, African-American vernacular, though this also may be from the role of the activity in establishing social hierarchy (from rank (n.)).
rank (v.): 1570s, "arrange in lines;" 1590s, "put in order, classify; assign a rank to," from rank (n.). Related: Ranked; ranking.
rank and file (n.): 1590s, in reference to the horizontal and vertical lines of soldiers marching in formation; thence generalized to "common soldiers" (1796) and "common people, general body" of any group (1860).
rankle (v.): c. 1300, "to fester," from Old French rancler, earlier raoncler, draoncler "to suppurate, run," from draoncle "abscess, festering sore," from Medieval Latin dracunculus, literally "little dragon," diminutive of Latin draco "serpent, dragon" (see dragon). The notion is of an ulcer caused by a snake's bite. Meaning "cause to fester" is from c. 1400. Related: Rankled; rankling.
ransack (v.): mid-13c., from a Scandinavian source akin to Old Norse rannsaka "to pillage," literally "search the house" (especially legally, for stolen goods), from rann "house," from Proto-Germanic *raznan (c.f. Gothic razn, Old English ærn "house;" see barn) + saka "to search," related to Old Norse soekja "seek" (see seek). Sense influenced by sack (v.). Related: Ransacked; ransacking.
ransom (n.): c. 1200, "sum paid for the release of a prisoner or captured man," from Old French ranson (Modern French rançon), earlier raenson "ransom, redemption," from Latin redemptionem (nominative redemptio) "a redeeming," from redimere (see redeem).
ransom: early 14c., from ransom (n.). Related: Ransomed; ransoming.
rant (v.): c. 1600, "to be jovial and boisterous," also "to talk bombastically," from Dutch randten (earlier ranten) "talk foolishly, rave," of unknown origin (compare German rantzen "to frolic, spring about"). Related: Ranted; ranting. Ranters "antinomian sect which arose in England c. 1645" is attested from 1651; applied 1823 to early Methodists. A 1700 slang dictionary has rantipole "a rude wild Boy or Girl" (also as a verb and adjective); to ride rantipole meant "The woman uppermost in the amorous congress" [Grose].
rant (n.): "boisterous, empty declamation; fierce or high-sounding language without much meaning or dignity of thought; bombast; a ranting speech," 1640s, from rant (v.).
rantallion (n.): "One whose scrotum is so relaxed as to be longer than his penis, i. e. whose shot pouch is longer than the barrel of his piece." ["Dictionary of the Vulgar Tongue," Grose, 1785]
rap (n.): c. 1300, "a quick, light blow, stroke," also "a fart" (late 15c.), native or borrowed from a Scandinavian source (compare Danish rap, Swedish rapp "light blow"); either way probably of imitative origin (compare slap, clap).

Slang meaning "rebuke, blame, responsibility" is from 1777; specific meaning "criminal indictment" (as in rap sheet, 1960) is from 1903. To beat the rap is from 1927. Meaning "music with improvised words" first in New York City slang, 1979 (see rap (v.2)).
rap (v.1): mid-14c., "strike, smite, knock," from rap (n.). Related: Rapped; rapping. To rap (someone's) knuckles "give light punishment" is from 1749. Related: Rapped; rapping.
rap (v.2): "talk informally, chat," 1929, popularized c. 1965 in African-American vernacular, possibly first in Caribbean English and from British slang meaning "say, utter" (1879), originally "to utter a sudden oath" (1540s), ultimately from rap (n.). As a noun in this sense from 1898. Meaning "to perform rap music" is recorded by 1979. Related: Rapped; rapping.
rapable (adj.): 1972, from rape (v.) + -able.
rapacious (adj.): 1650s, from Latin rapaci-, stem of rapax "grasping," itself from stem of rapere "to seize" (see rapacity) + -ous. Related: Rapaciously; rapaciousness.
rapacity (n.): 1540s, from Middle French rapacité (16c.), from Latin rapacitatem (nominative rapacitas) "greediness," from rapax (genitive rapacis) "grasping, plundering," from rapere "seize" (see rapid).
rape (v.): late 14c., "seize prey; abduct, take by force," from rape (n.) and from Anglo-French raper (Old French rapir) "to seize, abduct," a legal term, probably from past participle of Latin rapere "seize, carry off by force, abduct" (see rapid).

Latin rapere was used for "sexually violate," but only very rarely; the usual Latin word being stuprare "to defile, ravish, violate," related to stuprum (n.), literally "disgrace." Meaning "to abduct (a woman), ravish;" also "seduce (a man)" is from early 15c. in English. Related: Raped; raping. Uncertain connection to Low German and Dutch rapen in the same sense.
rape (n.2): kind of cruciferous plant (Brassica napus), late 14c., from Old French rape, from Latin rapa, rapum "turnip," from PIE *rap- (source also of Greek hrapys "rape," Old Church Slavonic repa, Lithuanian rope, Middle Dutch roeve, Old High German ruoba, German Rübe "rape, turnip"). Usually grown to feed sheep, an oil made from it is used in cooking (see canola).
rape (n.1): early 14c., "booty, prey;" mid-14c., "forceful seizure; plundering, robbery, extortion," from Anglo-French rap, rape, and directly from Latin rapere "seize" (see rape (v.)). Meaning "act of abducting a woman or sexually violating her or both" is from early 15c., but perhaps late 13c. in Anglo-Latin.
Raphael: masc. proper name, Biblical archangel (Apocrypha), from Late Latin, from Greek Rhaphael, from Hebrew Repha'el, literally "God has healed," from rapha "he healed" + el "God." Raphaelesque (1832) is in reference to painter Raffaello Sanzio (1483-1520). See Pre-Raphaelite.
raphe (n.): "seam, suture" (medical), 1753, medical Latin, from Greek rhaphe "seam, suture (of a skull)," from rhaptein "to sew together, stitch" (see wrap (v.)).
rapid (adj.): 1630s, "moving quickly," from French rapide (17c.) and directly from Latin rapidus "hasty, swift, rapid; snatching; fierce, impetuous," from rapere "hurry away, carry off, seize, plunder," from PIE root *rep- "to snatch" (source also of Greek ereptomai "devour," harpazein "snatch away," Lithuanian raples "tongs"). Meaning "happening in a short time" is from 1780. Related: Rapidly; rapidness. Rapid-transit first attested 1852, in reference to street railways; rapid eye movement is from 1906.
rapidity (n.): 1650s, from French rapidité and directly from Latin rapiditatem (nominative rapiditas) "swiftness, rapidity, velocity," from rapidus "hasty, swift, rapid" (see rapid).
rapids (n.): 1765, from French rapides (see rapid); applied by French voyagers to rough, swift-flowing reaches in North American rivers.
rapier (n.): "light, sharp-pointed sword," 1550s, from Middle French rapière, from espee rapiere "long, pointed two-edged sword" (late 15c.), in which the adjective is of uncertain origin, perhaps from derisive use of raspiere "poker, scraper." Dutch, Danish rapier, German Rappier are from French.