Online Etymology Dictionary

gastronome (n.): 1823, from French gastronome, a back-formation from gastronomie (see gastronomy). Alternative gastronomer is recorded from 1820.
gastronomic (adj.): 1828, from French gastronomique, from gastronomie (see gastronomy). Related: Gastronomical; gastronomically.
gastronomy (n.): 1814, from French gastronomie, coined 1800 by Joseph de Berchoux (1762-1838) as title of poem on good living, after Gastrologia, title of a now-lost poem of antiquity, quoted by Athenaeus (see gastrology). Berchoux's word is from gaster + nomos "arranging, regulating." Related: Gastronomer.
gastropod (n.): 1826, gasteropod (modern spelling by 1854), from Modern Latin Gasteropoda, name of a class of mollusks, from Greek gaster (genitive gastros) "stomach" (see gastric) + pous (genitive podos) "foot" (see foot (n.)). From the ventral position of the mollusk's "foot."
gastrula (n.): 1877, Modern Latin, from Greek gaster (genitive gastros) "stomach" (see gastric) + Latin -ula, diminutive suffix. Related: Gastrulation.
gat (n.): "revolver," 1904, slang shortening of Gatling (gun); by 1880, gatlin was slang for a gun of any sort.
gate (n.): "opening, entrance," Old English geat (plural geatu) "gate, door, opening, passage, hinged framework barrier," from Proto-Germanic *gatan (cf. Old Norse gat "opening, passage," Old Saxon gat "eye of a needle, hole," Old Frisian gat "hole, opening," Dutch gat "gap, hole, breach," German Gasse "street"), of unknown origin. Meaning "money collected from selling tickets" dates from 1896 (short for gate money, 1820). Gate-crasher is from 1927. Finnish katu, Lettish gatua "street" are Germanic loan-words.
gate (v.): "provide with a gate," 1906, from gate (n.). Originally of moulds. Related: Gated (1620s). Gated community recorded by 1989 (earliest reference to Emerald Bay, Laguna Beach, Calif.
gateau (n.): 1845, from French gâteau "cake," from Old French gastel, from Frankish *wastil "cake," from Proto-Germanic *was-tilaz, from PIE *wes- "to eat, consume."
gatehouse (n.): "house for a gatekeeper," late 14c., from gate (n.) + house (n.).
gatekeeper (n.): 1570s, from gate + keeper. Figurative use by 1872.
gateway (n.): 1707, from gate + way. Figurative use from 1842.
gather (v.): Old English gadrian, gædrian "unite, agree, assemble; gather, collect, store up," used of flowers, thoughts, persons; from Proto-Germanic *gadurojan "bring together, unite" (cf. Old English gæd "fellowship, companionship," gædeling "companion;" Middle Low German gadderen; Old Frisian gaderia; Dutch gaderen "to gather," gade "spouse;" German Gatte "husband;" Gothic gadiliggs), from PIE *ghedh- "to unite, join" (see good (adj.). Change of spelling from -d- to -th- is 1500s, reflecting earlier change in pronunciation. Related: Gathered; gathering.
gatherer (n.): c.1200, agent noun from gather.
gathering (n.): "a meeting," mid-12c., from late Old English gaderung, verbal noun from gather.
Gatling gun: 1870, named for designer Dr. Richard Jordan Gatling (1818-1903); patented by 1862 but not used in American Civil War until the Petersburg campaign of June 1864 as an independent initiative by U.S. Gen. Ben Butler.
For the first time in this war, the Gatling gun was used by Butler in repelling one of Beauregard's midnight attacks. Dispatches state that it was very destructive, and rebel prisoners were very curious to know whether it was loaded all night and fired all day. ... Gatling, like Mann, has found it very difficult to get fair trials of his gun, and to have it introduced by the War Department, for the Government leaves all such things to the Ordnance Office, and that office is under the control of old fogies, who work by red tape, and who are slow to perceive the value of ordnance improvements, and still slower to introduce them into practice. ["Scientific American," June 18, 1864]
gator (n.): 1844, colloquial shortening of alligator.
GATT: 1947, acronym from General Agreement on Tariffs and Trade.
gau (n.): ancient German territorial and administrative division, originally comprising several villages, surviving in place names such as Breisgau and Oberammergau; also in gauleiter (from leiter "leader"), title of the local political leaders under the Nazi system. Cf. the first element in yeoman.
gauche (adj.): "awkward, tactless," 1751 (Chesterfield), from French gauche "left" (15c., replacing Old French senestre in that sense), originally "awkward, awry," from Middle French gauchir "turn aside, swerve," from Old French gaucher "trample, reel, walk clumsily," from Frankish *welkan "to full" (cloth), from Proto-Germanic *wankjan (cf. Old High German wankon, Old Norse vakka "to stagger, totter;" see wink (v.)).
gaucherie (n.): 1798, from French gaucherie, from gauche (see gauche).
gaucho (n.): 1824, from Spanish, probably from a native South American language, cf. Araucanian cauchu "wanderer."
gaud (n.): late 14c., "jest, joke, prank, trick;" also "fraud, deception, trick, artifice." Also "large, ornamental bead in a rosary" (mid-14c.); a bauble, trinket, plaything" (mid-15c.). In some senses, from gaudy (n.) (see gaudy). In some, from Latin gaudium "joy," gaude "rejoice thou" (in hymns), or from Old French gaudie, noun of action from gaudir. As a verb, "to furnish with gauds," from late 14c. Related: Gauded; gauding.
gaudily (adv.): 1610s, from gaudy + -ly (2).
gaudiness (n.): c.1600, from gaudy + -ness.
gaudy (adj.): "showy, tastelessly rich," 1580s, probably ultimately from Middle English gaudi "large, ornamental bead in a rosary" (early 14c.); but there is a parallel sense of gaudy as "full of trickery" (1520s), from Middle English gaud "deception, trick," from gaudi "a jest, trick," possibly from Anglo-French gaudir "be merry, scoff," from Latin gaudere "rejoice" (see joy).

Alternative etymology of the adjective is from Middle English gaudegrene "yellowish-green" (early 14c.), originally "green dye" obtained from a plant formerly known as weld, from a Germanic source (see weld (n.)), which became gaude in Old French. The English term supposedly shifted sense from "weld-dye" to "bright." As a noun, "feast, festival" 1650s, from gaudy day "day of rejoicing" (1560s).
gauge (v.): "ascertain by exact measurements," mid-15c., from Anglo-French gauge (mid-14c.), from Old North French gauger (Old French jauger), from gauge "gauging rod," perhaps from Frankish *galgo "rod, pole for measuring" or another Germanic source (cf. Old Norse gelgja "pole, perch," Old High German galgo; see gallows). Related: Gauged; gauging. The figurative use is from 1580s.
gauge (n.): "fixed standard of measure," early 15c. (surname Gageman is early 14c.), from Old North French gauge "gauging rod" (see gauge (v.)). Meaning "instrument for measuring" is from 1680s.
Gaul (n.): 1560s, from French Gaule, from Latin Gallia, from Gallus "a Gaul." Also used somewhat facetiously for "a Frenchman." Gauloise, popular brand of French cigarettes, dates to 1910.
Gaulish: 1650s (adj.); 1660s (n.), from Gaul + -ish.
gaunt (adj.): mid-15c. (as a surname from mid-13c.), from Middle French gant, of uncertain origin; perhaps from a Scandinavian source (cf. Old Norse gand "a thin stick," also "a tall thin man") and somehow connected with the root of gander. Connection also has been suggested to Old French jaunet "yellowish" [Middle English Dictionary].
gauntlet (n.1): "glove," early 15c., gantelet, from Old French gantelet (13c.) "gauntlet worn by a knight in armor," also a token of one's personality or person, and symbolizing a challenge, e.g. tendre son gantelet "throw down the gauntlet" (a sense found in English by 1540s); semi-diminutive or double-diminutive of gant "glove" (12c.), earlier wantos (7c.), from Frankish *wanth-, from Proto-Germanic *wantuz "glove" (cf. Middle Dutch want "mitten," East Frisian want, wante, Old Norse vöttr "glove," Danish vante "mitten"), which apparently is related to Old High German wintan, Old English windan "turn around, wind" (see wind (v.)).
The name must orig. have applied to a strip of cloth wrapped about the hand to protect it from sword-blows, a frequent practice in the Icelandic sagas. [Buck]
Italian guanto, Spanish guante are likewise ultimately from Germanic. The spelling with -u- was established from 1500s.
gauntlet (n.2): military punishment in which offender runs between rows of men who beat him in passing, 1660s, earlier gantlope (1640s), from Swedish gatlopp "passageway," from Old Swedish gata "lane" (see gate) + lopp "course," related to löpa "to run" (see leap). Probably borrowed by English soldiers during Thirty Years' War. Modern spelling, influenced by gauntlet (n.1), not fixed until mid-19c.
gauss: C.G.S. unit of intensity of a magnetic field, 1882, named for German mathematician Karl Friedrich Gauss (1777-1855). Related: Gaussage.
Gautama: surname of the Buddha, from Sanskrit Gotamah, properly a patronymic, literally "descendant of the greatest ox," from superlative of gauh "ox, bull, cow."
gauze (n.): 1560s, gais, from French gaze, conjectured to be from Arabic gazz "raw silk" [Barnhart], or from Gaza, Palestinian city associated with production of this fabric [Klein, Du Cagne].
gauzy (adj.): 1796, from gauze + -y (2). Related: Gauziness.
gavage (n.): 1889, from French gavage, from gaver "to stuff" (17c.; see gavotte).
gave: past tense of give.
gavel (n.): "small mallet used by presiding officers at meetings," 1805, American English, of unknown origin; perhaps connected with German dialectal gaffel "brotherhood, friendly society," from Middle High German gaffel "society, guild," related to Old English gafol "tribute," giefan "to give" (see habit). But in some sources gavel also is identified as a type of mason's tool, in which case the extended meaning may be via freemasonry. As a verb, by 1887, from the noun.
gavotte (n.): lively dance, 1690s, from French gavotte (17c.), from Old Provençal gavoto "mountaineer's dance," from gavot, a local name for an Alpine resident, literally "boor, glutton," from gaver "to stuff, force-feed poultry," from Old Provençal gava "crop." From the same source is French gavache "coward, dastard."
gawk (v.): 1785, American English, perhaps from gaw, a survival from Middle English gowen "to stare" (c.1200), from a Scandinavian source akin to Old Norse ga "to heed," from Proto-Germanic *gawon-, from PIE *ghow-e- "to honor, revere, worship" (see favor (n.)); and altered perhaps by gawk hand (see gawky). Liberman writes that it "need not have been derived from gowk. It is possibly another independent imitative formation with the structure g-k. Related: Gawked; gawking.
gawky (adj.): "awkward, ungainly," 1724, from gawk hand "left hand" (1703), perhaps a contraction of gaulick, thus "gaulish hand," derogatory slang that could have originated during some period of strained Anglo-French relations, i.e. most of recorded history.
gawp (n.): "fool, simpleton," 1825, perhaps from the verb meaning "to yawn, gape" (as in astonishment), which is attested from 1680s, a dialectal survival of galp (c.1300), which is related to yelp or gape.
gay (adj.): late 14c., "full of joy, merry; light-hearted, carefree;" also "wanton, lewd, lascivious" (late 12c. as a surname, Philippus de Gay), from Old French gai "joyful, happy; pleasant, agreeably charming; forward, pert" (12c.; cf. Old Spanish gayo, Portuguese gaio, Italian gajo, probably French loan-words). Ultimate origin disputed; perhaps from Frankish *gahi (cf. Old High German wahi "pretty"), though not all etymologists accept this. Meaning "stately and beautiful; splendid and showily dressed" is from early 14c. The word gay by the 1890s had an overall tinge of promiscuity -- a gay house was a brothel. The suggestion of immorality in the word can be traced back at least to the 1630s, if not to Chaucer:
But in oure bed he was so fressh and gay
Whan that he wolde han my bele chose.
Slang meaning "homosexual" (adj.) begins to appear in psychological writing late 1940s, evidently picked up from gay slang and not always easily distinguished from the older sense:
After discharge A.Z. lived for some time at home. He was not happy at the farm and went to a Western city where he associated with a homosexual crowd, being "gay," and wearing female clothes and makeup. He always wished others would make advances to him. ["Rorschach Research Exchange and Journal of Projective Techniques," 1947, p.240]
The association with (male) homosexuality likely got a boost from the term gay cat, used as far back as 1893 in American English for "young hobo," one who is new on the road, also one who sometimes does jobs.
"A Gay Cat," said he, "is a loafing laborer, who works maybe a week, gets his wages and vagabonds about hunting for another 'pick and shovel' job. Do you want to know where they got their monica (nickname) 'Gay Cat'? See, Kid, cats sneak about and scratch immediately after chumming with you and then get gay (fresh). That's why we call them 'Gay Cats'." [Leon Ray Livingston ("America's Most Celebrated Tramp"), "Life and Adventures of A-no. 1," 1910]
Quoting a tramp named Frenchy, who might not have known the origin. Gay cats were severely and cruelly abused by "real" tramps and bums, who considered them "an inferior order of beings who begs of and otherwise preys upon the bum -- as it were a jackal following up the king of beasts" [Prof. John J. McCook, "Tramps," in "The Public Treatment of Pauperism," 1893], but some accounts report certain older tramps would dominate a gay cat and employ him as a sort of slave. In "Sociology and Social Research" (1932-33) a paragraph on the "gay cat" phenomenon notes, "Homosexual practices are more common than rare in this group," and gey cat "homosexual boy" is attested in N. Erskine's 1933 dictionary of "Underworld & Prison Slang" (gey is a Scottish variant of gay).

The "Dictionary of American Slang" reports that gay (adj.) was used by homosexuals, among themselves, in this sense since at least 1920. Rawson ["Wicked Words"] notes a male prostitute using gay in reference to male homosexuals (but also to female prostitutes) in London's notorious Cleveland Street Scandal of 1889. Ayto ["20th Century Words"] calls attention to the ambiguous use of the word in the 1868 song "The Gay Young Clerk in the Dry Goods Store," by U.S. female impersonator Will S. Hays, but the word evidently was not popularly felt in this sense by wider society until the 1950s at the earliest.
"Gay" (or "gai") is now widely used in French, Dutch, Danish, Japanese, Swedish, and Catalan with the same sense as the English. It is coming into use in Germany and among the English-speaking upper classes of many cosmopolitan areas in other countries. [John Boswell, "Christianity, Social Tolerance, and Homosexuality," 1980]
Gay as a noun meaning "a (usually male) homosexual" is attested from 1971; in Middle English it meant "excellent person, noble lady, gallant knight," also "something gay or bright; an ornament or badge" (c.1400).
gaydar (n.): by 1996, in gay literature, from gay + radar.
gayety (n.): see gaiety.
Gaylord: masc. proper name, also a surname (from early 13c.), also Galliard, from Old French Gaillart, from Proto-Germanic *Gailhard "lofty-hard," or Old French gaillard "lively, brisk, gay, high-spirited."
Gaza: Arabic form of Hebrew 'az "force, strength." Gaza Strip was created by the division of 1949.
gaze (v.): late 14c., probably of Scandinavian origin (cf. Norwegian, Swedish dialectal gasa "to gape"), perhaps related somehow to Old Norse ga "heed" (see gawk). Related: Gazed; gazing.