Online Etymology Dictionary

Shannon: river in Ireland, the name is something like "old man river," from a Proto-Celtic word related to Irish sean "old" (see senile).
Syriac (adj.): c. 1600, from Latin syraicus, from Greek syraikos "Syrian, of or pertaining to Syria," (see Syria). As the name of an ancient Semitic language, from 1610s.
Talladega: city in Alabama, U.S., from Muskogee /talati:ki/, a tribal town name, from /(i)talwa/ "tribal town" + /-atiiki/ "at the edge, border."
Tecumseh: Native American leader (1768-1813), his name is Shawnee (Algonquian), perhaps literally "flies across;" compare Menominee /takhamehse:w/ "flies straight across."
Zanzibar: island off East Africa, from Zengi, name of a local people, said to mean "black," + Arabic barr "coast, shore." Related: Zanzibari.
Fibonacci (adj.): 1891 in reference to a series of numbers in which each is equal to the sum of the preceding two, from name of Leonardo Fibonacci (fl. c. 1200) Tuscan mathematician.
febicches (pl.n.): also fibicches, fybicches, febicchis, febucches "contrivances, cheating tricks," late 14c., of unknown origin. Quirk suggests perhaps from Pebichios, name of an old alchemist.
fletcherism (n.): dietary system emphasizing very thorough mastication, 1903, from -ism + name of Horace Fletcher (1849-1919), U.S. health enthusiast. Related: Fletcherize; fletcherized.
Valencia: place in Spain, Roman Valentia Edetanorum "fort of the Edetani," a local people name; the first element from Latin valentia "strength" (see valence (n.)).
froggy (n.): 1822 as a familiar name for a frog, from frog (n.1) + -y (3). As a disparaging term for a Frenchman by 1857.
Galen: celebrated Greek physician of 2c.; his work still was a foundation of medicine in the Middle Ages and his name is used figuratively for doctors.
Istria: peninsula near the head of the Adriatic Sea, Latin Istria, from Istaevones, name of a Germanic people there, of unknown origin. Related: Istrian (c. 1600).
horse-flesh (n.): also horseflesh, c. 1400, "horses collectively;" 1530s, "meat from a horse," from horse (n.) + flesh (n.). From 1520s as a color-name.
Granada: Moorish kingdom, after 1492 a Spanish province, named for its city, which was founded in 8c. by the Arabs on the site of Roman Illiberis. The name is said to be from Latin granatum "pomegranate," either from fruit grown in the region or from some fancied resemblance. Others connect the name to Moorish karnattah, said to mean "hill of strangers." The Roman name is said to be Iberian and represent cognates of Basque hiri "town" + berri "new," and it survives in the name of the surrounding Sierra Elvira. Related: Granadine.
knuckle-duster (n.): face-busting, hand-protecting metal knuckle-guard, 1857, from knuckle (n.) + duster, name of a type of protective coat worn by workmen.
Helga: fem. proper name, from Old Norse Helga, literally "holy," from Proto-Germanic *hailaga, from PIE *kailo- (see health). A doublet of Olga.
Leighton: place name (and surname), Old English leahtun, from earlier *leactun "a garden," from leac (see leek) + tun "farm, settlement, enclosure" (see town (n.)).
ladybird (n.): also lady-bird, 1590s, "sweetheart," a term of endearment, from lady + bird (n.2). As the name of a type of beetle, 1670s, the earlier form of ladybug.
lightfoot (adj.): "speedy, nimble," also a name for a ship or a rabbit, c. 1300 (c. 1200 as a surname) from light (adj.1) + foot (n.).
Linguaphone (n.): proprietary name of a language-learning program involving phonograph records, 1908, from Latin lingua "language, tongue" (see lingual) + ending from gramophone, etc.
David: masc. proper name, in Old Testament second king of Israel and Judah and author of psalms, from Hebrew Dawidh, literally "darling, beloved friend." The name was common in England and Scotland by 12c., but much earlier in Wales. A nickname form was Dawe, hence surnames Dawson, Dawkins. A top 10 list name for boys born in the U.S. from 1934 to 1992.
Acadian: 1705, from Acadia, Latinized form of Acadie, French name of Nova Scotia, probably from Archadia, the name given to the region by Verrazano in 1520s, from Greek Arkadia, emblematic in pastoral poetry of a place of rural peace (see Arcadian); the name may have been suggested to Europeans by the native Micmac (Algonquian) word akadie "fertile land." The Acadians, expelled by the English in 1755, settled in large numbers in Louisiana (see Cajun, which is a corruption of Acadian).
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.
Jill: fem. proper name, Middle English Jille, Jylle, Gille, etc., familiar shortening of Jillian, Gillian, which represent the common Middle English pronunciation of Juliana (see Gillian). A very popular name for girls in medieval England, hence its use as a familiar, almost generic, name for a girl (early 15c.; paired with Jack since mid-15c.).
kitty (n.1): "young cat, child's pet name for a cat," 1719, variant of kitten, perhaps influenced by kitty "girl, young woman" (c. 1500), which is originally a pet form of fem. proper name Catherine. Kitty Hawk, the place in the Outer Banks of North Carolina where the Wright Brothers first flew, apparently is a mangling of a native Algonquian name; it also has been written as Chicahauk.
Iberia: from Latin Iberia, the ancient name of the large southwestern peninsula of Europe, from Greek Iberes, the name of a Celtic people of ancient Spain. An identical name was given to an Asiatic people near the Caucasus in what is now Georgia. Of unknown origin in both uses, but the word as applied in Spain is believed to be related to that of the River Ebro. Related: Iberian (c. 1600 as a noun; 1610s as an adjective).
Jemima: fem. personal name, biblical daughter of Job, from Hebrew Yemimah, literally "dove" (compare Arabic yamama). The Aunt Jemima ready-mix food product in U.S. was advertised from c. 1918; the name (and image) was on baking powder advertisements by 1896. It is the title of a minstrel song credited to Joe Lang, but this is not mentioned before 1901. Previously Aunt Jemima was a name in various works of fiction and poetry, without racial aspect.
ogham (n.): also ogam, ancient Irish form of writing, 1620s, from Irish ogham, from Old Irish ogam, said to be from name of its inventor, Ogma Mac Eladan. But this appears to be from Celt. *Ogmios, perhaps from PIE *og-mo- "furrow, track," thus metaphorically "incised line." This could be the source of the name of the writing style, which looks like a series of cuts or incised lines, and the inventor's name thus might be folk etymology. Related: Oghamic.
Oliver: masc. personal name, in medieval lore the name of one of Charlemagne's peers, friend of Roland, from French Olivier, from Middle Low German Alfihar, literally "elf-host, elf-army," from alf "elf" (see elf) + hari "host, army" (see harry (v.)). Cognate with Anglo-Saxon name Ælfhere. Form influenced in Old French by olivier "olive tree."
heather (n.): early 14c., hathir, from Old English *hæddre, Scottish or northern England dialect name for Calluna vulgaris, probably altered by heath, but real connection to that word is unlikely [Liberman, OED]. Perhaps originally Celtic. As a fem. proper name little used in U.S. before 1935, but a top-15 name for girls born there 1971-1989.
Nestor: name for "old king renowned for wise counsel," 1580s, from Greek, name of the aged and wise hero in the "Iliad," king of Pylus, who outlived three generations. Klein says the name is literally "one who blesses," and is related to nostimos "blessed;" Watkins connects it with the root of the first element in nostalgia.
Rebecca: fem. proper name, biblical wife of Isaac, mother of Jacob and Esau, from Late Latin Rebecca, from Greek Rhebekka, from Hebrew Ribhqeh, literally "connection" (compare ribhqah "team"), from Semitic base r-b-q "to tie, couple, join" (compare Arabic rabaqa "he tied fast"). Rebekah, the form of the name in Authorized Version, was taken as the name of a society of women (founded 1851 in Indiana, U.S.) as a complement to the Odd Fellows.
dirk (n.): c. 1600, perhaps from Dirk, the proper name, which was used in Scandinavian for "a picklock." But the earliest spellings were dork, durk (Johnson, 1755, seems to be responsible for the modern spelling), and the earliest association is with Highlanders, however there seems to be no such word in Gaelic, where the proper name is biodag. Another candidate is German dolch "dagger." The masc. given name is a variant of Derrick, ultimately from the Germanic compound in Dietrich.
Albigensian: c. 1600, "relating to the Albigenses," Catharist religious reformers of southern France c.1020-1250, Medieval Latin Albigenses (12c.), from French Albi, name of the town in Languedoc where they lived and were first condemned as heretics (1176). The town name is from Roman personal name Albius, from Latin albus "white" (see alb).
hemlock (n.): poisonous plant native to Europe, transplanted to North America, Old English (Kentish) hemlic, earlier hymlice, hymblice, name of a poisonous plant; of unknown origin. Liberman suggests from root hem- "poison," perhaps with the plant name suffix -ling or -ig. As the name of the poison derived from the plant, c. 1600. The North American fir tree so called by 1670s in New England, from resemblance of the position and tenuity of its leaves to those of the plant.
Thalia: fem. proper name, from Latinized form of Greek Thaleia, "the joyful Muse," presiding over comedy and idyllic poetry, literally "the blooming one," fem. proper name from adjective meaning "blooming, luxuriant, bounteous," from thallein "to bloom," related to thalia "abundance," thallos "young shoot" (see thallus). Also the name of one of the three Graces, patroness of festive meetings.
Pelagian: 1530s (n.); 1570s (adj.), from Medieval Latin Pelagianus, from Pelagius, Latinized form of the name of 4c. British monk who denied the doctrine of original sin. Combated by Augustine, condemned by Pope Zosimus in 418 C.E. His name in Welsh was said to have been Morgan, literally "sea-dweller" (hence his Church name, from Greek pelagos "sea;" see pelagic). Related: Pelagianism.
Winchester: city in Hampshire, capital of Wessex and later of the Anglo-Saxon kingdom, Old English Uintancæstir (c.730), from Ouenta (c. 150), from Venta, a pre-Celtic name perhaps meaning "favored or chief place" + Old English ceaster "Roman town" (see Chester). As the name of a kind of breech-loading repeating rifle it is from the name of Oliver F. Winchester (1810-1880), U.S. manufacturer.
anaconda (n.): 1768, a name first used in English to name a Ceylonese python, it was applied erroneously to a large South American boa, called in Brazil sucuriuba. The word is of uncertain origin, and no snake name like it now is found in Sinhalese or Tamil. One suggestion is that it is a Latinization of Sinhalese henacandaya "whip snake," literally "lightning-stem" [Barnhart]. Another suggestion is that it represents Tamil anaikkonda "having killed an elephant" [OED].
citrus (adj.): 1825, from Modern Latin genus name, from Latin citrus "citron tree," name of an African tree with aromatic wood and lemon-like fruit, the first citrus fruit to become available in the West. The name, like the tree, is probably of Asiatic origin [OED]. But Klein traces it to Greek kedros "cedar," and writes that the change of dr into tr shows that the word came from Greek into Latin through the medium of the Etruscans. As a noun, "tree of the genus Citrus," from 1885.
Lothario: masc. proper name, Italian form of Old High German Hlothari, Hludher (whence German Luther, French Lothaire), literally "famous warrior," from Old High German lut (see loud) + heri "host, army" (see harry (v.)). As a characteristic name for a lady-killer, 1756, from the name of the principal male character of Nicholas Rowe's "The Fair Penitent" (1703).
Reuben: masc. proper name, Old Testament eldest son of Jacob and name of the tribe descended from him, from Greek Rouben, from Hebrew Reubhen, probably literally "Behold a son," from reu, imperative of ra'ah "he saw" + ben "a son." As a typical name of a farmer, rustic, or country bumpkin, from 1804. The reuben sandwich (1956) is "Not obviously connected" with the sense in rube [OED], possibly from Reuben's restaurant, a popular spot in New York's Lower East Side.
Mercedes-Benz: motorcar brand first marketed 1926 after merger of two earlier companies. The first part of the name, Mercedes, marketed as a car name from 1901, chosen by Austrian manufacturer Emil Jellinek for his daughter, Mercedes (1889-1929). The Benz is from the other company, from name of Karl Benz, creator of the Benz Patent Motorwagen (1886). The surname is built from a familiar form of Berthold, Benedict, or Bernhard.
pimpernel (n.): c. 1400, from Old French pimprenelle, earlier piprenelle (12c.) and directly from Medieval Latin pipinella name of a medicinal plant. This is perhaps from *piperinus "pepper-like" (so called because its fruits resemble peppercorns), a derivative of Latin piper "pepper" (see pepper (n.)); or else it is a corruption of bipinnella, from bipennis "two-winged." The Scarlet Pimpernel was the code name of the hero in an adventure novel of that name published 1905.
phaeton (n.): type of light four-wheeled carriage, 1742, from French (1735), from Greek Phaethon name of the son of Helios and Clymene, who tried to drive his father's sun-chariot but crashed after almost setting fire to the whole earth. His name is literally "shining," from phaein "to shine, gleam," from phaos "light" (see fantasy). Earlier as a name for a reckless driver (1590s).
tyrannosaurus (n.): carnivorous Cretaceous bipedal dinosaur, 1905, Modern Latin genus name, coined by H.F. Osborn (published 1906 in "Bulletin of the American Museum of Natural History" XXI, p.259) from comb. form of Greek tyrannos "tyrant" (see tyrant) + -saurus. Abbreviated name T. rex attested by 1970 (apparently first as the band name).
Muhammad: 1610s, Mohammed, Arabic masc. proper name, literally "the Praiseworthy," name of the prophet of Islam (c.570-632). The earliest forms of his name in English were Mahum, Mahimet (c. 1200); originally also used confusedly for "an idol." Wyclif has Macamethe (c. 1380), and Makomete also turns up in 14c. documents. Mahomet was common until 19c.; see Mohammed.
Istanbul: Turkish name of Constantinople; it developed in Turkish 16c. as a corruption of Greek phrase eis tan (ten) polin "in (or to) the city," which is how the local Greek population referred to it. Turkish folk etymology traces the name to Islam bol "plenty of Islam." Greek polis "city" has been adopted into Turkish as a place-name suffix -bolu.
Stepin Fetchit: type of stereotypical black roles in Hollywood, or in popular culture generally, from stage name (a play on step and fetch it) of popular black vaudeville actor Lincoln Theodore Perry (1902-1985), who first appeared in films under that name in "In Old Kentucky" (1927). Perry said he took the name from a racehorse on which he'd won some money.
Sharon: fem. proper name; from the name of the fertile coastal plain between Jaffa and Mount Carmel, from Hebrew, short for yesharon, properly "the Plain," from stem of yashar "was straight, was even" (compare Hebrew mishor "level land, plain"). A top-10 list name for girls born in the U.S. between 1943 and 1949.