Online Etymology Dictionary

getaway (n.): "escape," 1852, originally in fox hunting; see get + away. Of prisoners or criminals from 1893. Verbal phrase get away "escape" is attested from c.1300.
Gethsemane: name of a garden on the Mount of Olives in Jerusalem [Matt. xxvi:36-46], from Greek Gethsemane, from Aramaic gath shemani(m) "oil-press."
Gettysburg: town in southern Pennsylvania, U.S., 1800 (earlier it was Gettys-town), founded 1780s by Gen. James Gettys and named for him. Civil War battle there was fought July 1-3, 1863. The Gettysburg Address was given Nov. 19, 1863, and was being called that by 1865, though before Lincoln’s assassination the term tended to refer to Edward Everett’s full oration that preceded Lincoln’s short speech.
gewgaw (n.): early 13c., giuegaue, contemptuous reduplication, possibly connected with Old French gogue "rejoicing, jubilation; joke, prank, mockery, game;" or jou-jou "toy," baby-talk word, from jouer "to play," from Latin jocare (see joke).
gey (adj.): a Scottish variant of gay, sometimes used 18c.-19c. with a sense of "considerable, pretty much, considerably." Cf. gray/grey.
geyser (n.): 1780, from Icelandic Geysir, name of a hot spring in the valley of Haukadal, literally "the gusher," from Old Norse geysa "to gush," from Proto-Germanic *gausjan, from PIE *gheus-, from root *gheu- "to pour" (see found (v.2)).
Ghana: since 1957, name of the former Gold Coast; from the name of a former tribal chieftain, whose name itself is a form of a royal title, hence, "king."
ghastly (adj.): c.1300, gastlich, from gast (adj.), past participle of gasten "to frighten," from Old English gæstan "to torment, frighten" (see ghost) + -lich "-ly." Spelling with gh- developed 16c. from confusion with ghost. As an adverb, from 1580s. Related: Ghastliness.
ghat (n.): also ghaut, from Hindi, "pass, mountain," from Sanskrit ghattah "landing place," of unknown origin.
ghawazee (n.): Egyptian dancing-girls, 1799, from Arabic gawazi, plural of gaziya.
ghazi (n.): Muslim warrior fighting the infidels, 1735, from Arabic ghazi, properly participle of ghaza (stem gh-z-w) "he made war."
gherkin (n.): small cucumber used for pickling, 1660s, from early modern Dutch gurken, augurken (late 16c.) "small pickled cucumber," from East Frisian augurk "cucumber," probably from a Balto-Slavic source (cf. Polish ogórek "cucumber"), possibly ultimately from Medieval Greek angourion "a kind of cucumber," said to be from Persian angarah [Klein, etc.], but OED seems to regard this as unlikely. A Dutch source says the Greek is from a word for "immature" and that the vegetable originated in northern India and came to Eastern Europe via the Byzantine Empire. The Dutch suffix is perhaps the diminutive -kin, though some regard it as a plural affix, with the Dutch word mistaken for a singular in English. The -h- was added 1800s to preserve the hard "g" pronunciation.
ghetto (n.): 1610s, "part of a city to which Jews were restricted," especially in Italy, from Italian ghetto "part of a city to which Jews are restricted," various theories of its origin include: Yiddish get "deed of separation;" special use of Venetian getto "foundry" (there was one near the site of that city's ghetto in 1516); a clipped word from Egitto "Egypt," from Latin Aegyptus (presumably in memory of the exile); or Italian borghetto "small section of a town" (diminutive of borgo, of Germanic origin, see borough). Extended by 1899 to crowded urban quarters of other minority groups (especially blacks in U.S. cities). As an adjective by 1903 (modern slang usage from 1999). Ghetto-blaster "large, portable stereo" is from 1982.
Ghibelline: adherent of the emperor in medieval Italy, 1570s, from German Waiblingen, seat of the Hohenstaufens in Württemberg. The name was said to have been used as a rallying cry by partisans of Conrad III at the Battle of Weinsberg (1140). See Guelph.
ghost (n.): Old English gast "soul, spirit, life, breath; good or bad spirit, angel, demon," from Proto-Germanic *ghoizdoz (cf. Old Saxon gest, Old Frisian jest, Middle Dutch gheest, Dutch geest, German Geist "spirit, ghost"), from PIE root *gheis- "to be excited, amazed, frightened" (cf. Sanskrit hedah "wrath;" Avestan zaesha- "horrible, frightful;" Gothic usgaisjan, Old English gæstan "to frighten"). This was the usual West Germanic word for "supernatural being," and the primary sense seems to have been connected to the idea of "to wound, tear, pull to pieces." The surviving Old English senses, however, are in Christian writing, where it is used to render Latin spiritus, a sense preserved in Holy Ghost. Modern sense of "disembodied spirit of a dead person" is attested from late 14c. and returns the word toward its ancient sense.

Most Indo-European words for "soul, spirit" also double with reference to supernatural spirits. Many have a base sense of "appearance" (e.g. Greek phantasma; French spectre; Polish widmo, from Old Church Slavonic videti "to see;" Old English scin, Old High German giskin, originally "appearance, apparition," related to Old English scinan, Old High German skinan "to shine"). Other concepts are in French revenant, literally "returning" (from the other world), Old Norse aptr-ganga, literally "back-comer." Breton bugelnoz is literally "night-child." Latin manes probably is a euphemism.

The gh- spelling appeared early 15c. in Caxton, influenced by Flemish and Middle Dutch gheest, but was rare in English before mid-16c. Sense of "slight suggestion" (in ghost image, ghost of a chance, etc.) is first recorded 1610s; that in ghost writing is from 1884, but that term is not found until 1919. Ghost town is from 1908. To give up the ghost "die" was in Old English. Ghost in the machine was Gilbert Ryle's term (1949) for "the mind viewed as separate from the body."
ghostly (adj.): Old English gastlic "spiritual, holy; clerical;" also "ghostly, spectral, pertaining to or characteristic of a ghost;" see ghost + -ly (1). Related: Ghostliness.
ghoul (n.): 1786, in the English translation of Beckford's "Vathek," from Arabic ghul, an evil spirit that robs graves and feeds on corpses, from ghala "he seized."
ghoulish (adj.): 1840, from ghoul + -ish. Related: Ghoulishly; ghoulishness.
giant (n.): c.1300, from Old French geant, earlier jaiant (12c.), from Vulgar Latin *gagantem (nominative gagas), from Latin gigas "giant," from Greek gigas (genitive gigantos), one of a race of savage beings, sons of Gaia and Uranus, eventually destroyed by the gods, probably from a pre-Greek language. Replaced Old English ent, eoten, also gigant. The Greek word was used in Septuagint to refer to men of great size and strength, hence the expanded use in modern languages. Of very tall persons from 1550s; of persons who have any quality in extraordinary degree, from 1530s.
In þat tyme wer here non hauntes Of no men bot of geauntes. [Wace's Chronicle, c.1330]
giantess (n.): late 14c., from giant + -ess.
giaour (n.): 1560s, Turkish term of contempt for non-Muslims, from Persian gaur, variant of gabr "fire-worshipper," originally applied to the adherents of the Zoroastrian religion.
Gib: familiar abbreviation of Gilbert. As a typical name for a cat, from c.1400.
gib (n.): type of iron hook, 1560s, of unknown origin. As a piece of wood or metal to hold something else in place, from 1795.
gibber (v.): c.1600, probably a back-formation from gibberish. Related: Gibbered; gibbering.
gibberish (n.): 1550s, imitative of the sound of chatter, probably influenced by jabber. Used early 17c. of the language of rogues and gypsies.
gibbet (n.): early 13c., "gallows," from Old French gibet "gallows; a bent stick," diminutive of gibe "club," perhaps from Frankish *gibb "forked stick." The verb meaning "to kill by hanging" is from 1590s. Related: Gibbeted; gibbeting. "Originally synonymous with GALLOWS sb., but in later use signifying an upright post with projecting arm from which the bodies of criminals were hung in chains or irons after execution" [OED].
gibbon (n.): 1770, from French gibbon (18c.), supposedly from a word in the French colonies of India but not found in any language there. Brought to Europe by Marquis Joseph-François Dupleix (1697-1763), French governor general in India 1742-54. The surname is Old French Giboin, from Frankish *Geba-win "gift-friend," or in some cases a diminutive of Gibb, itself a familiar form of Gilbert.
gibbous (adj.): c.1400, "bulging, convex," from Late Latin gibbus "hunchbacked," from Latin gibbus "hump, hunch," of uncertain origin. Of the moon from early 15c.; also used from 15c. of hunchbacks.
gibe (v.): alternative spelling of jibe.
giblet (n.): see giblets.
giblets (n.): mid-15c. (in singular, gybelet), from Old French gibelet "game stew," of uncertain origin, perhaps from Frankish *gabaiti "hunting with falcons," related to Old High German beizan "to fly a falcon," literally "to cause to bite," from bizzan "to bite."
Gibraltar: 1590s, ancient Calpe, captured 710 C.E. by Saracen leader Tariq, renamed Jebel el Tarik "the Mountain of Tarik," hence the English name. A British possession since 1704. Figurative of impregnability by 1856.
Gibson girl: "woman considered stylish late 1890s and early 1900s," 1901, named for U.S. artist and illustrator Charles Dana Gibson (1867-1944), whose main model was his wife, Irene Langhorne. The Gibson cocktail (attested by 1914) is in some stories ascribed to him, but the origin of that term is unknown.
giclee: c.1991, from French giclée, from gicler "to squirt, spurt, spray."
giddily (adv.): mid-13c., from giddy + -ly (2).
giddiness (n.): late 13c., "thoughtless folly;" see giddy + -ness. Meaning "dizziness" is late 14c.
giddy (adj.): Old English gidig, variant of gydig "insane, mad, stupid, possessed (by a spirit)," probably from Proto-Germanic *gud-iga-, from *gudam "god" + *-ig "possessed." Meaning "having a confused, swimming sensation" is from 1560s. Meaning "elated" is from 1540s.
Gideon: Bible propagation society, 1906, formally Christian Commercial Young Men's Association of America, founded 1899. It takes its name from Gideon, Israelite judge and warrior [Judg. vi:11-viii:25], from Hebrew Gidh'on, literally "feller," from stem of gadha "he cut off, hewed, felled."
gif (n.): 1987, acronym from Graphics Interchange Format.
gift (n.): mid-13c. (c.1100 in surnames), from a Scandinavian source, cf. Old Norse gift, gipt "gift, good luck," from Proto-Germanic *giftiz (cf. Old Saxon gift, Old Frisian jefte, Middle Dutch ghifte "gift," German Mitgift "dowry"), from PIE root *ghabh- "to give or receive" (see habit).

For German Gift "poison," see poison. Old English cognate gift meant "bride-price, marriage gift (by the groom), dowry" (Old English noun for "giving, gift" was related giefu). Sense of "natural talent" is c.1300, perhaps from earlier sense of "inspiration" (late 12c.). As a verb from 16c., especially in gifted. As a verb, giftwrap (also gift-wrap) attested by 1936.
gifted (adj.): "talented," 1640s, past participle adjective from gift.
gig (n.1): "light carriage, small boat," 1790, perhaps, on notion of bouncing, from Middle English ghyg "spinning top" (in whyrlegyg, mid-15c.), also "giddy girl" (early 13c., also giglet), from Old Norse geiga "turn sideways," or Danish gig "spinning top."
gig (n.2): "job," first used by jazz musicians, attested from 1915 but said to have been in use c.1905; of uncertain origin. As a verb, by 1939. Related: Gigged; gigging.
giga-: arbitrary word-forming element meaning "billion" in the metric system, 1947, from Greek gigas "giant" (see giant).
gigabyte (n.): 1982, from giga- + byte.
gigantic (adj.): 1610s, "pertaining to giants," from Latin gigant- stem of gigantem, from gigas "giant" (see giant) + -ic. Replaced earlier gigantine (c.1600), gigantical (c.1600), giantlike (1570s). Of material or immaterial things, actions, etc., by 1797.
gigantism (n.): 1885, from Latin gigant- (see gigantic) + -ism.
gigaton (n.): by 1977, from giga- + ton.
giggle (v.): c.1500, probably imitative. Related: Giggled; giggling; giggly. As a noun from 1570s.
giglot (n.): "lewd, wanton woman" (mid-14c.); later "a giddy, romping girl;" of unknown origin; cf. gig (n.1).