Online Etymology Dictionary

garcon (n.): c. 1300, "a boy, a youth" (early 13c. as a surname), from Old French garçun "menial, servant-boy, page; man of base condition," ["in jocular use, 'lad'" - OED]; objective case of gars (11c.; Modern French garçon "boy, bachelor, single man; waiter, porter"). This comes, perhaps via Gallo-Romance, from Frankish *wrakjo- or another Germanic source, from Proto-Germanic *wrakjon (source also of Old High German recko, Old Saxon wrekkio "a banished person, exile;" English wretch). From c. 1400 as "young male servant, squire, page." Meaning "a waiter" (especially one in a French restaurant) is a reborrowing from 1788.
garden (n.): late 13c. (late 12c. in surnames), from Old North French gardin "(kitchen) garden; orchard; palace grounds" (Old French jardin, 13c., Modern French jardin), from Vulgar Latin hortus gardinus "enclosed garden," via Frankish *gardo or some other Germanic source, from Proto-Germanic *gardaz (source also of Old Frisian garda, Old Saxon gardo, Old High German garto, German Garten "a garden," Old English geard, Gothic gards "enclosure;" see yard (n.1)). Italian giardino, Spanish jardin are from French.

As an adjective from c. 1600. Garden-party "company attending an entertainment on the lawn or garden of a private house" is by 1843. Garden-variety in figurative sense first recorded 1928. To lead someone up the garden path "entice, deceive" is attested by 1925. Garden-glassgarden-glass "round dark glass reflective globe (about a foot and a half across) placed on a pedestal, used as a garden ornament," is from 1842.
garden (v.): "to lay out and cultivate a garden," 1570s, from garden (n.). Related: Gardened; gardening.
gardener (n.): late 13c. (early 12c. as a surname), from Old North French *gardinier (Old French jardineor "gardener," 12c., Modern French jardinier), from gardin "(kitchen) garden" (see garden (n.)). Compare German Gärtner. An Old English word for it was wyrtweard, literally "plant-guard."
gardenia (n.): shrub genus, 1757, Modern Latin, named for Scottish-born American naturalist Dr. Alexander Garden (1730-1791), Vice President of the Royal Society, + abstract noun ending -ia.
gardening (n.): 1570s, verbal noun from garden (v.).
garderobe (n.): also garde-robe, "wardrobe," early 14c., from Old French garderobe "wardrobe; alcove; dressing-room" (Old North French warderobe; see wardrobe).
gare (n.): French for "train station," 1840 in French, from earlier sense "river port, pier" (17c.), verbal noun from garer "to (supply with) shelter," in Middle French also "to dock ships" (see garage (n.)).
garfish (n.): mid-15c., from gar + fish (n.).
gargantuan (adj.): "enormous," 1590s, from Gargantua, name of the voracious giant in Rabelais' novels, supposedly from Spanish/Portuguese garganta "gullet, throat," which is from the same imitative root as gargle (v.).
gargle (v.): 1520s, from Middle French gargouiller "to gurgle, bubble" (14c.), from Old French gargole "throat, waterspout," which is perhaps from garg-, imitative of throat sounds, + *goule, dialect word for "mouth," from Latin gula "throat." Related: Gargled; gargling. The earlier, native, form of the word was Middle English gargarize (early 15c.), from Latin gargarizare, from Greek gargarizein.
gargle (n.): 1650s, "liquid used in gargling," from gargle (v.).
gargoyle (n.): "grotesque carved waterspout," connected to the gutter of a building to throw down water clear of the wall, common in 13c.-16c. buildings; late 13c., gargoile, also garguile, gargule, etc., "carved mouth of a rain spout, a gargoyle," from Old French gargole, gargoule "throat;" also "carved downspout," in the form of a serpent or some other fanciful shape, also from Medieval Latin gargola, gargulio (see gargle (v.)). "An archaic spelling, retained in books; better gargoil or, in more modern form gargel" [Century Dictionary].
Garibaldi: 1862, blouse worn by women in imitation of red shirts worn by followers of Giuseppe Garibaldi (1807-1882), liberator of Italy.
garish (adj.): "showy, dazzling," especially "glaringly vulgar and gaudy," 1540s, of unknown origin, possibly from obsolete Middle English gawren "to stare" (c. 1200), which is of uncertain origin (perhaps from Old Norse gaurr "rough fellow") + -ish. Related: Garishly; garishness.
garland (n.): c. 1300 (mid-13c. in Anglo-Latin), "wreath of flowers," also "crown of gold or silver," from Old French garlande "garland," probably from a Frankish frequentative form of *weron "adorn, bedeck," from *wiara-, *weara- "wire" (on the notion of "ornament of refined gold," properly "of twisted gold wire"), from Proto-Germanic *wira-, *wera-, suffixed form of PIE *wei- (1) "to turn, twist" (see wire (n.)). Compare Middle High German wieren "adorn, bedeck." The word is found in many forms in the Romanic language, such as Old Spanish guarlanda, French guirlande, Italian ghirlanda, Portuguese guirnalda.
garland (v.): early 15c., "to make a garland;" 1590s, "to crown with a garland," from garland (n.). Related: Garlanded; garlanding.
garlic (n.): Middle English garlek, from Old English garlec (West Saxon), garleac (Mercian), "garlic," from gar "spear" (in reference to the clove), see gar, + leac "leek" (see leek). Garlic-bread is from 1958.
garlicky (adj.): 1775, from garlic + -y (2). The -k- perhaps to preserve the hard -c-, but garlick was a former alternative spelling.
garment (n.): c. 1400, "any article of clothing," reduced form of garnement (early 14c.), from Old French garnement "garment, attire, clothes" (12c.), from garnir "fit out, provide, adorn" (see garnish (v.)).
garner (n.): "a granary," late 12c., gerner, from Old French gernier, metathesized variant of grenier "storehouse, loft for grain," from Latin granarium (usually plural, granaria) "store-house for grain" (see granary).
garner (v.): late 15c., "to store grain," from garner (n.). Related: Garnered; garnering.
garnet (n.): mid-15c., metathesized form of gernet "the gem garnet" (early 14c.), from Old French grenate, gernatte, granate "garnet," also an adjective, "of a dark red color," from Medieval Latin granatum "garnet; of dark red color," perhaps abstracted from the Medieval Latin or Old French words for pomegranate, from the stone's resemblance either to the shape of the seeds or the color of the pulp. Or the word might be from Medieval Latin granum "grain," in its sense of "cochineal, red dye." A widespread word: Spanish and Portuguese granate, Italian granato, Dutch granaat, German Granat.
garnish (v.): late 14c., "to decorate, adorn, beautify," also in Middle English "equip (a place) for defense; arm (oneself) for battle; prepare to defend," from Old French garniss-, present participle stem of garnir "provide, furnish; fortify, reinforce" (11c.), from Frankish *warnjan, from Proto-Germanic *warnon "be cautious, guard, provide for" (source also of Old High German warnon "to take heed," Old English warnian "to take warning, beware;" see weir, and compare warn).

Sense evolution is from "arm oneself" to "fit out" to "embellish," which was the earliest meaning in English. Culinary sense of "to decorate a dish for the table" predominated after c. 1700. Older meaning survives in legal sense of "to warn or serve notice of attachment of funds" (1570s). Related: Garnished; garnishing.
garnish (n.): late 14c., "set of tableware" (probably a dozen; usually pewter), from garnish (v.). Sense of "embellishments to food" is from 1670s.
garnishee (n.): "one who owes debts and has been warned legally to not pay money or transfer property which has been awarded to his creditor," 1620s, from garnish (v.) in the legal sense + -ee.
garnishment (n.): 1550s, "embellishment, adornment, decoration," from garnish (v.) + -ment. Legal financial sense from 17c. The verbal noun garnishing also was used in the sense "ornament, that which decorates" (late 14c.).
garret (n.): c. 1300, garite, "turret, small tower on the roof of a house or castle," from Old French garite "watchtower, place of refuge, shelter, lookout," from garir "defend, preserve," which is from a Germanic source (compare Old English warian "to hold, defend," Gothic warjan "forbid," Old High German warjan "to defend"), from Proto-Germanic *warjan, from PIE root *wer- (5) "to cover" (see warrant (n.)). Meaning "room on uppermost floor of a house," especially a room with a sloping roof, is from early 14c. See attic. As the typical wretched abode of a poor poet, by mid-18c.
Garrett: surname, from mid-13c., from Gerald or Gerard, with loss of consonant.
garrison (n.): c. 1300, "store, treasure," from Old French garison "defense, protection, safety, security; crops, food; salvation; healing, recovery, cure" (Modern French guérison "cure, recovery, healing") from garir "defend" (see garret). Meaning "fortified stronghold" is from early 15c.; that of "body of troops in a fortress" is from mid-15c., a sense taken over from Middle English garnison "body of armed men stationed in a fort or town to guard it" (late 14c.), from Old French garnison "provision, munitions," from garnir "to furnish, provide" (see garnish (v.)).
garrison (v.): "to place troops in," 1560s, from garrison (n.). Related: Garrisoned; garrisoning.
garrot (n.): kind of sea-duck, 1829, from French garrot (1757), a word of unknown origin.
garrote (n.): also garrotte, 1620s, "Spanish method of capital punishment by strangulation," from Spanish garrote "stick for twisting cord" (the method used in the execution), of unknown origin. Perhaps from Old French guaroc "club, stick, rod, shaft of a crossbow," probably ultimately Celtic, but possibly from Frankish *wrokkan "to twist" (cognate with Middle Dutch wroken "to twist").
I have no hesitation in pronouncing death by the garrot, at once the most manly, and the least offensive to the eye. [Major John Richardson, "British Legion," 1837]
garrote (v.): "to execute with a garrote," 1845, from garrote (n.); sense of "choke senseless and then rob" is from 1852. Related: Garotted; garotting.
garrulity (n.): 1580s, from Middle French garrulité, from Latin garrulitatem (nominative garrulitas) "chattering, loquacity," from garrulus "talkative" (see garrulous).
garrulous (adj.): 1610s, from Latin garrulus "talkative, chattering," from garrire "to chatter," from PIE root *gar- "to call, cry," of imitative origin (compare Greek gerys "voice, sound," Ossetic zar "song," Welsh garm, Old Irish gairm "noise, cry"). Related: Garrulously; garrulousness.
garter (n.): "tie or fastening to keep a stocking in place on the leg," early 14c., from Old North French gartier "band just above or below the knee" (Old French jartier, 14c., Modern French jarretière), from garet/jaret "bend of the knee," perhaps from Gaulish (compare Welsh garr "leg"). Garter in reference to the highest order of knighthood (mid-14c.) is from the Order of the Garter, the earliest records of which are entirely lost, but which according to Froissart was established c. 1344 by Edward III, though the usual story of how it came about is late (1614) and perhaps apocryphal. Garter-snake (1775, U.S.) so called from resemblance to a ribbon. Garter belt attested by 1913.
garter (v.): mid-15c., from garter (n.). Related: Gartered; gartering.
garth (n.): "small piece of enclosed ground," a northern and western English dialect word, mid-14c., from Old Norse garðr "yard, courtyard, fence," cognate of Old English geard (see yard (n.1)).
Gary: masc. proper name, also a surname, from Norman form of Old Norse geiri, Old Danish geri "spear" (see gar).
gas (n.1): 1650s, from Dutch gas, probably from Greek khaos "empty space" (see chaos). The sound of Dutch "g" is roughly equivalent to that of Greek "kh." First used by Flemish chemist J.B. van Helmont (1577-1644), probably influenced by Paracelsus, who used khaos in an occult sense of "proper elements of spirits" or "ultra-rarified water," which was van Helmont's definition of gas.
Hunc spiritum, incognitum hactenus, novo nomine gas voco ("This vapor, hitherto unknown, I call by a new name, 'gas.'") [Helmont, Ortus Medicinae]
Modern scientific sense began 1779, with later secondary specialization to "combustible mix of vapors" (1794, originally coal gas); "anesthetic" (1894, originally nitrous oxide); and "poison gas" (1900). Meaning "intestinal vapors" is from 1882. "The success of this artificial word is unique" [Weekley]. Slang sense of "empty talk" is from 1847; slang meaning "something exciting or excellent" first attested 1953, from earlier hepster slang gasser in the same sense (1944). Gas also meant "fun, a joke" in Anglo-Irish and was used so by Joyce (1914). Gas-works is by 1817. Gas-oven is from 1851 as a kitchen appliance; gas-stove from 1848.
gas (v.): 1886, "to supply with (illuminating) gas," from gas (n.1). Sense of "poison with gas" is from 1889 as an accidental thing, from 1915 as a military attack. In old slang also "talk nonsense, lie to." Related: Gassed; gassing; gasses.
gas (n.2): short for gasoline, American English, by 1905. Gas-pump is from 1925; gas-pedal "automobile accelerator" is by 1908; gas-station "fueling station for an automobile" is from 1916.
gas-guzzler (n.): car with low fuel-efficiency, 1973, American English, from gas (short for gasoline) + guzzler.
gas-house (n.): also gashouse, 1880 as a power-generating station, from gas (n.1) + house (n.). By 1926, emblematic of a run-down district of a U.S. city, a typical abode of criminals and gangsters.
gas-light (n.): 1808, from (illuminating) gas (n.1) + light (n.).
gas-mask (n.): 1915, from (poison) gas (n.1) + mask (n.).
Gascon: "native of Gascony," late 14c., from Middle French Gascon, from Vulgar Latin *Wasco, from Latin Vasco, singular of Vascones, the name of the ancient inhabitants of the Pyrénées (see Basque). Among the French, proverbially a boastful people, hence gasconade (n.), "bragging talk" (1709).
gasconade (n.): "a boast, boastful talk, bluster," 1709, from French gasconade (see Gascon + -ade); from gasconner (16c.) "to boast, brag," literally "to talk like a Gascon." As a verb in English from 1727.
gaselier (n.): "gas-burning chandelier," 1849, from gas (n.1) on model of chandelier.