Online Etymology Dictionary

wormwood: c.1400, folk etymology of O.E. wermod "wormwood," related to vermouth, but the ultimate etymology is unknown. Cf. O.S. wermoda, Du. wermoet, O.H.G. werimuota, Ger. Wermut. Weekley suggests wer "man" + mod "courage," from its early use as an aphrodisiac. Figurative use, however, is usually in reference to its bitter aftertaste. Perhaps because of the folk etymology, it formerly was used to protect clothes and bedding from moths and fleas. "A medecyne for an hawke that hath mites. Take the Iuce of wormewode and put it ther thay be and thei shall dye." ["Book of St. Albans," 1486]
cockroach: 1624, folk etymology of Sp. cucaracha "chafer, beetle," from cuca "kind of caterpillar." Folk etymology is from caca "excrement."
"A certaine India Bug, called by the Spaniards a Cacarootch, the which creeping into Chests they eat and defile with their ill-sented dung" [Capt. John Smith, "Virginia," 1624].
hop (n.2): "opium," 1887, from Cantonese nga-pin (pronounced HAH-peen) "opium," a Chinese folk etymology of the Eng. word opium, lit. "crow peelings." Re-folk-etymologized back into Eng. by association with hop (n.1).
folklore: 1846, coined by antiquarian William J. Thoms (1803-85) as an Anglo-Saxonism (replacing popular antiquaries) and first published in the "Athenaeum" of Aug. 22, 1846, from folk + lore. This word revived folk in a modern sense of "of the common people, whose culture is handed down orally," and opened up a flood of compound formations, eg. folk art (1921), folk-hero (1899), folk-medicine (1898), folk-tale (1891), folk-song (1847), folk-dance (1912). Folk-music is from 1889; in reference to the branch of modern popular music (originally associated with Greenwich Village in New York City) it dates from 1958.
piepowder: 1220, "wayfarer, itinerant merchant, etc.," folk etymology alteration of M.L. pede-pulverosus, lit. "dusty-footed."
Pict: an ancient people of Great Britain, 1387, from L.L. Picti (late 3c., probably a nickname given them by Roman soldiers), usually taken as derived from picti "painted," but probably ultimately from the Celtic name of the tribe, perhaps Pehta, Peihta, lit. "the fighters" (cf. Gaul. Pictavi, who gave the name to the Fr. city of Poitiers). They painted and tattooed themselves, which may have suggested a Roman folk-etymology alteration of the name. The O.E. name for the people was Peohtas.
"In Scottish folk-lore the Pechts are often represented as a dark pygmy race, or an underground people; and sometimes identified with elves, brownies, or fairies." [OED]
hangnail: 1678, probably folk etymology from O.E. agnail "a corn on the foot," from PIE *angh- "tight, painfully constricted, painful."
Tijuana: from the name of a Diegueño (Yuman) village, written Tiajuan in 1829; deformed by folk-etymology association with Sp. Tia Juana "Aunt Jane."
Bern: Swiss capital, probably originally from PIE root *ber- "marshy place," but by folk etymology from Ger. Bär "bear."
Acheron: 1580s, fabled river of the Lower World in Gk. mythology. The name probably means "marsh-like" (cf. akherousai "marshlike water"); the derivation from akhos "woe" is considered folk etymology.
johnny-cake: 1739, Amer.Eng., of unknown origin, perhaps from Shawnee cake, from the Indian tribe. Folk etymology since 1775, however, connects it to journey cake.
Gullah: "of or pertaining to blacks on the sea-islands of Georgia and South Carolina," 1739 (first attested as a male slave's proper name), of uncertain origin. Early 19c. folk etymology made it a shortening of Angola (homeland of many slaves) or traced it to a W. African tribal group called the Golas.
Uriah: masc. proper name, in O.T., the Hittite husband of Bathsheba; of non-Hebrew (possibly Horite) origin, but explained by folk etymology as Heb. Uriyyah, lit. "flame of the Lord." Uriah Heep, character from Dickens' "David Copperfield" (1850) sometimes is invoked as the type of a hypocritically humble person.
piggyback: 1838, probably a folk-etymology alteration of pick pack (1565), which perhaps is from pick, a dial. variant of pitch (v.).
delicate: late 14c., from L. delicatus "alluring, delightful, dainty," also "addicted to pleasure," of unknown origin; related by folk etymology (and perhaps genuinely) to deliciæ "a pet," and delicere "to allure, entice." Meaning "feeble in constitution" is c.1400; that of "easily broken" is recorded from 1560s.
gentian: O.E., from L. gentiana, said by Pliny to be named for Gentius, king of ancient Illyria who discovered its properties. This is likely a folk-etymology, but the word may be Illyrian, since the suffix -an frequently occurs in Illyrian words.
Lilith: female evil spirit, in medieval Heb. folklore the first wife of Adam, from Heb. Lilith, from Akkad. Lilitu, which is connected by folk etymology with Heb. laylah "night."
jackanapes: c.1449, "a monkey," also "an impertinent, conceited fellow;" apparently from Jack of Naples, but whether this is some specific personification or folk etymology of jack (n.) + ape is unknown.
pennyroyal: herb, 1530, alteration by folk etymology of Anglo-Fr. puliol real; for second element see royal; first element ultimately from L. puleglum "thyme."
mongoose: "snake-killing ichneumon of India," 1698, perhaps via Port., from an Indic language (cf. Mahrathi mangus "mongoose"), probably ult. from Dravidian (cf. Telugu mangisu, Kanarese mungisi). The form of the Eng. word altered by folk-etymology.
headlong: 1482, from hed "head" + suffix -ling (see grovel). Altered by folk etymology on pattern of sidelong, etc.
Chamorro: indigenous people of Guam and the Marianas Islands, from Sp. Chamorro, lit. "shorn, shaven, bald." Supposedly because the men shaved their heads, but the name also has been connected to native Chamoru, said to mean "noble," so perhaps Chamorro is a Sp. folk etymology.
banausic: "merely mechanical," coined 1845 from Gk. banausikos "pertaining to mechanics," from banausos "artisan, mere mechanical," hence (to the Greeks) "base, ignoble;" perhaps lit. "working by fire," from baunos "furnace, forge" (but Klein dismisses this as folk etymology and calls it "of uncertain origin").
Bombay: city in western India, from Port., and popularly explained as Port. bom bahia "good bay," but that seems folk etymology (for one, the adj. is masc. and the n. is fem.), and the more likely candidate is the local Mumbadevi "Goddess Mumba," a Hindu deity worshipped there. The city's name officially changed to Mumbai in 1995.
patch (2): "fool, clown," 1549, perhaps from It. pazzo "fool," which is possibly from O.H.G. barzjan "to rave." Form perhaps infl. by folk-etymology from patch (1), on notion of a fool's patched garb.
Pegasus: winged horse in Gk. mythology, late 14c., from L., from Gk. Pegasos, usually said to be from pege "spring, font" (pl. pegai), especially in "springs of Ocean," near which Medusa was said to have been killed by Perseus (Pegasus sprang from her blood). But this may be folk etymology, and the suffix -asos suggests a pre-Gk. origin.
corduroy: 1780, Amer.Eng., probably from cord + obs. 17c. duroy, a coarse fabric made in England. Folk etymology is from *corde du roi "the king's cord," but this is not attested in Fr., where the term for the cloth was velours à côtes. Applied in U.S. to a road of logs across swampy ground (1822).
gyrfalcon: 1209, from O.Fr. gerfauc, probably from Frankish, from P.Gmc. *ger (cf. O.H.G. gir "vulture") + L. falco "hawk." Folk etymology connects it with L. gyrus (see gyre) in reference to "circling" in the air.
petrel: 1676, pitteral, modern spelling first recorded 1703 by Dampier, who says the bird was so called from its way of flying with its feet just skimming the surface of the water, which recalls the apostle's walk on the sea of Galilee (Matt. xiv:28); if so, it likely was formed in Eng. as a dim. of Peter (L.L. Petrus). If this is folk-etymology, the true source of the name is undiscovered. Fr. pétrel (1760) probably is from Eng.
ailurophobia: "morbid fear of cats," 1905, from Gk. -phobia "fear" + ailouros "cat," of unknown origin. Folk etymology connects it with aiolos "quick-moving" + oura "tail." Related: Ailurophile (1931).
mandrake: c.1150, from M.L. mandragora, from L. mandragoras, from Gk. mandragoras, probably from a non-I.E. word. Folk etymology associated the second element with dragoun and substituted native drake in its place. The forked root is thought to resemble a human form and is said to shriek when pulled from the ground.
pickaxe: 1428, folk etymology alteration (influenced by axe) of M.E. picas (1256), via Anglo-Fr. piceis, from O.Fr. pocois (11c.), from M.L. picosa "pick," related to L. picus "woodpecker."
ballast: "heavy material used to steady a ship," 1520s, from M.E. bar "bare" (in this case "mere") + last "a load, burden," or borrowed from identical terms in North Sea Gmc. and Scand. (cf. O.Dan. barlast, 14c.). Du. balg-last "ballast," lit. "belly-load," is a folk-etymology corruption.
behemoth: late 14c., huge biblical beast (Job xl.15), from L. behemoth, from Heb. b'hemoth, usually taken as plural of intensity of b'hemah "beast." But the Heb. word is perhaps a folk etymology of Egyptian pehemau, lit. "water-ox," the name for the hippopotamus.
leech (1): "bloodsucking aquatic worm," from O.E. læce (Kentish lyce), of unknown origin (with a cognate in M.Du. lake). Commonly regarded as a transf. use of leech (2), but the O.E. forms suggest a distinct word, which has been assimilated to leech (2) by folk etymology. Figuratively applied to human parasites since 1784.
samovar: 1830, from Rus. samovar, lit. "self-boiler," from sam "self" + varit "to boil," from O.Slav. variti "to cook;" but this is perhaps folk-etymology if the word is from Tatar sanabar "tea-urn."
fetlock: early 14c., fetlak, from a Gmc. source (cf. M.H.G. fizlach, Ger. Fiszloch), perhaps related to the root of Ger. fessel "pastern." The M.E. dim. suffix -ok (from O.E. -oc) was misread and the word taken in folk etymology as being a compound of feet and lock (of hair).
wedlock: O.E. wedlac "pledge-giving, marriage vow," from wed + -lac, noun suffix meaning "actions or proceedings, practice," attested in about a dozen O.E. compounds (cf. feohtlac "warfare"), but this is the only surviving example. Suffix altered by folk etymology through association with lock. Meaning "condition of being married" is recorded from early 13c.
Peloponnesus: peninsula of southern Greece, c.1490, from L., from Gk. Peloponnesos, second element apparently nesos "island," first element said to be named for Pelops, son of Tantalus, who killed him and served him to the gods as food (they later restored him to life). The proper name is probably from pellos "dark" + ops "face, eye." But the association with the peninsula name likely is folk etymology.
gonorrhea: 1526, from L.L. gonorrhoia, from gonos "seed" + rhoe "flow," from rhein "to flow" (see rheum). Mucus discharge was mistaken for semen. In early records often Gomoria, etc., from folk etymology association with biblical Gomorrah.
salmon: c.1200, from O.Fr. salmun, from L. salmonem (nom. salmo) "a salmon," possibly originally "leaper," from salire "to leap," though some dismiss this as folk etymology. Another theory traces it to Celtic. Replaced O.E. læx, from PIE *lax, the more usual word for the fish (see lox).
avocado: 1763, from Sp. avocado, altered (by folk etymology influence of earlier Sp. avocado "lawyer," from same L. source as advocate) from earlier aguacate, from Nahuatl ahuakatl "testicle." So called for its shape. As a color, first attested 1947.
shamefaced: 1555, "modest, bashful," folk etymology alteration of shamefast, from O.E. scamfæst "bashful," lit. "restrained by shame," or else "firm in modesty," from shame + -fæst, adjectival suffix (see fast (adj.)).
panther: c.1220, from O.Fr. pantere (12c.), from L. panthera, from Gk. panther, probably of Oriental origin, cf. Skt. pundarikam "tiger," probably lit. "the yellowish animal," from pandarah "whitish-yellow." Folk etymology derivation from Gk. pan- "all" + ther "beast" led to many curious fables.
bridegroom: O.E. brydguma "suitor," from bryd "bride" + guma "man" (cf. O.N. gumi, O.H.G. gomo, cognate with L. homo "man"). Ending altered 16c. by folk etymology after groom "groom, boy, lad" (q.v.). Common Gmc. term, except in Goth., which used bruþsfaþs, lit. "bride's lord."
meerkat: 1481, "monkey," from Du. meerkat "monkey" (related to O.H.G. mericazza), apparently from meer "lake" + kat "cat." But cf. Hindi markat, Skt. markata "ape," which could serve as a source of a Teutonic folk-etymology, even though the word was in Gmc. long before any known direct contact with India. First applied to the small South African mammals in 1801.
ogham: ancient Ir. form of writing, 1627, from Ir. ogham, from O.Ir. 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 may be folk-etymology.
Jerusalem: holy city in Palestine, from Gk. Hierousalem, from Heb. Yerushalayim, lit. "foundation of peace," from base of yarah "he threw, cast" + shalom "peace." Jerusalem "artichoke" is folk etymology of It. girasole "sunflower."
asparagus: late O.E. sparage, from M.L. sparagus, from L. asparagus, Gk. asparagos, probably from PIE base *sp(h)er(e)g- "to spring up" (though perhaps from a non-Gk. source). Respelled c.1600 to conform with classical Latin. Sparrowgrass is 17c. folk etymology, persisting into 19c., during which time asparagus had "an air of stiffness and pedantry" [John Walker, "Critical Pronouncing Dictionary," 1791].
Istanbul: Turk. name of Constantinople, a corruption of Gk. phrase eis tan (ten) polin "into the city," which is how the local Gk. population referred to it. Picked up in Turkish 16c., though Turk. folk etymology traces the name to Islam bol "plenty of Islam." Gk. polis "city" has been adopted into Turk. as a place-name suffix as -bolu.