Online Etymology Dictionary

rich (adj.): Old English rice "strong, powerful; great, mighty; of high rank," in later Old English "wealthy," from Proto-Germanic *rikijaz (source also of Old Norse rikr, Swedish rik, Danish rig, Old Frisian rike "wealthy, mighty," Dutch rijk, Old High German rihhi "ruler, powerful, rich," German reich "rich," Gothic reiks "ruler, powerful, rich"), borrowed from a Celtic source akin to Gaulish *rix, Old Irish ri (genitive rig) "king," from PIE root *reg- "move in a straight line," hence, "direct, rule" (see rex).

The form of the word was influenced in Middle English by Old French riche "wealthy, magnificent, sumptuous," which is, with Spanish rico, Italian ricco, from Frankish *riki "powerful," or some other cognate Germanic source.

Old English also had a noun, rice "rule, reign, power, might; authority; empire." The evolution of the word reflects a connection between wealth and power in the ancient world. Of food and colors, from early 14c.; of sounds, from 1590s. Sense of "entertaining, amusing" is recorded from 1760. The noun meaning "the wealthy" was in Old English.
get-rich-quick (adj.): in reference to projects or schemes, American English, 1891, when there was a rash of them, from the verbal phrase.
richness (n.): mid-14c., from rich (adj.) + -ness.
richly (adv.): Old English ricelice "powerfully, sumptuously;" see rich (adj.) + -ly (2).
riches (n.): "valued possessions, money, property," c. 1200, modified from richesse (12c.), a singular form misunderstood as a plural, from Old French richesse, richece "wealth, opulence, splendor, magnificence," from riche (see rich (adj.)). The Old French suffix -esse is from Latin -itia, added to adjectives to form nouns of quality (compare fortress).
Richard: masc. proper name, Middle English Rycharde, from Old French Richard, from Old High German Ricohard "strong in rule," from Proto-Germanic *rik- "ruler" (see rich) + *harthu "hard," from PIE *kar-o- (see hard (adj.)). "One of the most popular names introduced by the Normans. Usually Latinized as Ricardus, the common form was Ricard, whence the pet form Rick, etc." ["Dictionary of English Surnames"]
Roderick: also Roderic, masc. proper name, from Old High German Hroderich, literally "ruling in fame," from hruod- "fame, glory" + Proto-Germanic *rikja "rule" (see rich). Italian and Spanish Rodrigo, Russian Rurik are from German.
Alaric: Visigothic masc. proper name, literally "all-ruler," from Proto-Germanic *ala- "all" (see all) + *rikja "rule" (see rich).
enrich (v.): late 14c., "to make wealthy," from Old French enrichir "enrich, enlarge," from en- "make, put in" (see en- (1)) + riche "rich" (see rich). Figurative sense "supply with abundance of something desirable" is from 1590s. Meaning "to fertilize" is from c. 1600. Scientific sense of "to increase the abundance of a particular isotope in some material" is first attested 1945. Related: Enriched; enriching.
nouveau riche: 1813, French, literally "new rich." Opposite noveau pauvre is attested from 1965. Ancient Greek had the same idea in neo-ploutos "newly become rich."
stinking (adj.): late 14c., earlier stinkend, from Old English stincende; present participle adjective from stink (v.). Modifying drunk, first attested 1887; stinking rich dates from 1956.
strike (v.): Old English strican (past tense strac, past participle stricen) "pass lightly over, stroke, smooth, rub," also "go, move, proceed," from Proto-Germanic *strikan- (source also of Old Norse strykva "to stroke," Old Frisian strika, Middle Dutch streken, Dutch strijken "to smooth, stroke, rub," Old High German strihhan, German streichen), from PIE root *streig- "to stroke, rub, press" (see strigil). Related to streak and stroke, and perhaps influenced in sense development by cognate Old Norse striuka.

Sense of "to deal a blow" developed by early 14c.; meaning "to collide" is from mid-14c.; that of "to hit with a missile" is from late 14c. Meaning "to cancel or expunge" (as with the stroke of a pen) is attested from late 14c. A Middle English sense is preserved in strike for "go toward." Sense of "come upon, find" is from 1835 (especially in mining, well-digging, etc., hence strike it rich, 1854). Baseball sense is from 1853. To strike a balance is from the sense "balance accounts" (1530s).

Meaning "refuse to work to force an employer to meet demands" is from 1768, perhaps from notion of striking or "downing" one's tools, or from sailors' practice of striking (lowering) a ship's sails as a symbol of refusal to go to sea (1768), which preserves the verb's original sense of "make level, smooth."
Richter scale: 1938, devised by U.S. seismologist Charles Francis Richter (1900-1985).
money-bag (n.): 1560s, from money + bag (n.). Meaning "rich person" is from 1818. Related: moneybags.
vulgarian (n.): "rich person of vulgar manners," 1804, from vulgar (adj.) + -ian.
Dis: Roman underworld god, from Latin Dis, contracted from dives "rich," which is related to divus "divine, god," hence "favored by god." Compare Pluto and Old Church Slavonic bogatu "rich," from bogu "god."
Rockefeller (n.): "immensely rich man," 1938, in reference to U.S. financier and philanthropist John D. Rockefeller (1839-1937).
opulent (adj.): c. 1600, from Middle French opulent, from Latin opulentem (nominative opulens) "wealthy, rich," from opulentus (see opulence).
Lipari: large island north of Sicily, largest of the Aeolian Islands, probably somehow related to Greek liparos "fat; rich" (see liparo-).
Dives: traditional name for a rich man, late 14c., from Latin dives "rich (man);" see Dis. Used in Luke xvi in Vulgate and commonly mistaken as the proper name of the man in the parable. Related to divus "divine," and originally meaning "favored by the gods" (see divine (adj.)).
liparo-: before vowels lipar-, word-forming element meaning "oily," from Greek liparos "oily, shiny with oil, fatty, greasy," used of rich soil and smooth skin; figuratively "rich, comfortable; costly, splendid," from lipos "fat" (see lipo-).
rhino (n.): short for rhinoceros, 1884. As slang for "cash" (also rino) 1680s, of unknown origin. Hence cant rhinocerial "rich" [Grose, 1788].
plenteous (adj.): c. 1300, plentivous, from Old French plentiveus "fertile, rich" (early 13c.), from plentif "abundant," from plentee "abundance" (see plenty). Related: Plentifully; plentifulness.
wealthy (adj.): late 14c., "happy, prosperous," from wealth + -y (2). Meaning "rich, opulent" is from early 15c. Noun meaning "wealthy persons collectively" is from late 14c.
simonize (v.): 1921, from Simoniz, trademark for a type of car polish invented by George Simons, who along with Elmer Rich of the Great Northern Railway organized Simons Manufacturing Company to sell it in Chicago, U.S.A., in 1910. Rich and his brother, R.J. Rich, acquired sole ownership two years later.
Camembert (n.): type of soft, rich cheese, 1878, from name of village near Argentan, Normandy, where it originally was made. The place name is Medieval Latin Campus Maimberti "field of Maimbert" (a West Germanic personal name).
eglantine (n.): "sweet briar," c. 1400, from French églantine, from Old French aiglent "dog rose," from Vulgar Latin *aquilentus "rich in prickles," from Latin aculeus "spine, prickle," diminutive of acus "needle" (see acuity).
impecunious (adj.): "lacking in money," 1590s, from assimilated form of in- "not, opposite of" (see in- (1)) + Latin pecuniosus "rich," from pecunia "money, property" (see pecuniary). Related: Impecuniously; impecuniosity.
tokay (n.): 1710, rich sweet wine from the region of Tokay (Hungarian Tokaj) a town in Hungary. The name is perhaps Slavic, from tok "current," or Hungarian, from a Turkic personal name.
bonanza (n.): 1844, American English, from Spanish bonanza "a rich lode," originally "fair weather at sea, prosperity," from Vulgar Latin *bonacia, from Latin bonus "good" (see bene-).
Rothschild: "rich person," 1833, in reference to the international banking family descended from Mayer Amschel Rothschild (1744-1812) of Frankfurt. The surname is literally "red shield," a house name.
Ulrich: masc. proper name, German, from Old High German Uodalrich, literally "of a rich home," from uodal "home, nobility" (related to Old English æðele "noble," Old Norse oðal "home").
fruitcake (n.): also fruit-cake, 1838 in the literal sense "a rich, sweet cake containing fruit," from fruit + cake (n.). Slang meaning "lunatic person" is first attested 1952.
loaded (adj.): "drunk," slang, 1886, from past participle of load (v.), from expression take one's load "drink one's fill" (1590s). In the sense of "rich," loaded is attested from 1910.
Croesus: from Latinized form of Greek Kroisis, 6c. B.C.E. king of Lydia in Asia Minor, famously wealthy; hence "rich man" or in other allusions to riches, from late 14c.
Euboea: large island of Greece north of Attica and Boeotia, literally "rich in cattle," from eu- "good, well" (see eu-) + bous "ox, cow" (see cow (n.)). Related: Euboean.
jeunesse doree (n.): 1811, French jeunesse dorée "gilded youth, rich and fashionable young men," from jeunesse "youth," from jeune "young" (12c.), from Latin iuvenis "young" (see young (adj.)) + fem. of doré "gilded."
Letitia: fem. proper name, literally "gladness," from Latin laetitia "joy, exultation, rejoicing, gladness, pleasure, delight," from laetus "glad, happy; flourishing, rich," a word of unknown origin. On the assumption that "fat, rich" is the older meaning, this word has been connected to lardus "bacon" and largus "generous," but de Vaan finds this "a very artificial reconstruction." In 17c. English had a verb letificate "make joyful" (1620s), and Middle English had letification "action of rejoicing" (late 15c.).
lapis lazuli (n.): "azure-stone, rich ultramarine silicate stone," early 15c., from Middle Latin lapis lazuli, literally "stone of azure," from Latin lapis "a stone" (see lapideous) + Medieval Latin lazuli, genitive of lazulum, from Arabic lazuward (see azure).
nabob (n.): 1610s, "deputy governor in Mogul Empire," Anglo-Indian, from Hindi nabab, from Arabic nuwwab, honorific plural of na'ib "viceroy, deputy," from base n-w-b "to take someone's place." Also used of Europeans who came home from India having made a fortune there, hence "very rich man" (1764).
affluent (adj.): mid-15c., "flowing," from Middle French affluent (14c.) or directly from Latin affluentem (nominative affluens) "flowing toward, abounding, rich, copious," present participle of affluere "flow toward," from ad- "to" (see ad-) + fluere "to flow" (see fluent).
argosy (n.): 1570s, from Italian (nave) Ragusea "(vessel) of Ragusa," maritime city on the Dalmatian coast of the Adriatic (modern Dubrovnik in Croatia). Their large merchant ships brought rich Eastern goods to 16c. England. The city name sometimes was Aragouse or Arragosa in 16c. English.
affluence (n.): mid-14c., "a plentiful flowing, an abundance," from Old French affluence, from Latin affluentia "a flowing to," figuratively "affluence, abundance," noun of state from affluentem (nominative affluens) "flowing toward, abounding, rich, copious" (see affluent). Sense of "wealth" attested from c. 1600, from notion of "a plentiful flow" (of the gifts of fortune).
Madeleine: fem. proper name, variation of Madeline. The kind of small, rich confection is attested from 1845, said in OED to be named for Madeleine Paulmier, 19c. French pastry cook; any use with a sense of "small thing that evokes powerful nostalgia" is due to Proust (1922).
Edith: fem. proper name, Old English Eadgyð, from ead "riches, prosperity, good fortune, happiness" + guð "war." A fairly common name; it survived through the Middle Ages, probably on the popularity of St. Eadgyð of Wilton (962-84, abbess, daughter of King Edgar of England), fell from favor 16c., was revived in fashion late 19c. Old English ead (also in eadig "wealthy, prosperous, fortunate, happy, blessed; perfect;" eadnes "inner peace, ease, joy, prosperity") became Middle English edy, eadi "rich, wealthy; costly, expensive; happy, blessed," but was ousted by happy. Late Old English, in its grab-bag of alliterative pairings, had edye men and arme "rich men and poor."
Egypt: Old English Egipte "the Egyptians," from French Egypte, from Greek Aigyptos "the river Nile, Egypt," from Amarna Hikuptah, corresponding to Egyptian Ha(t)-ka-ptah "temple of the soul of Ptah," the creative god associated with Memphis, the ancient city of Egypt.

Strictly one of the names of Memphis, it was taken by the Greeks as the name of the whole country. The Egyptian name, Kemet, means "black country," possibly in reference to the rich delta soil. The Arabic is Misr, which is derived from Mizraim, the name of a son of Biblical Ham.
jet (n.2): also jetstone, "deep black lignite," mid-14c., from Anglo-French geet, Old French jaiet "jet, lignite" (12c., Modern French jais), from Latin gagates, from Greek gagates lithos "stone of Gages," town and river in Lycia in Asia Minor. Formerly supposed to be magnetic. From mid-15c. as "a deep, rich, glossy black color" (the color of jet) and as an adjective.
pall (n.): Old English pæll "rich cloth or cloak, purple robe, altar cloth," from Latin pallium "cloak, coverlet, covering," in Tertullian, the garment worn by Christians instead of the Roman toga; related to pallo "robe, cloak," palla "long upper garment of Roman women," perhaps from the root of pellis "skin." Notion of "cloth spread over a coffin" (mid-15c.) led to figurative sense of "dark, gloomy mood" (1742).
-phagous: word-forming element meaning "eating, feeding on," from Latin -phagus, from Greek -phagos "eater of," from phagein "to eat," literally "to have a share of food," from PIE root *bhag- "to share out, apportion, distribute," also "to get a share" (cognates: Sanskrit bhajati "assigns, allots, apportions, enjoys, loves," bhagah "allotter, distributor, master, lord," bhaksati "eats, drinks, enjoys;" Persian bakhshidan "to give;" Old Church Slavonic bogatu "rich").
Morton: surname, from the many Mortons on the map of England, literally "moor or marsh settlement." Morton's Fork (1759) is in reference to John Morton (c. 1420-1500), archbishop of Canterbury, who levied forced loans under Henry VII by arguing the obviously rich could afford to pay and the obviously poor clearly were living frugally and thus had savings and could pay, too.