Online Etymology Dictionary

gut-bucket (adj.): in reference to jazz, "earthy," by 1929, supposedly originally a reference to the buckets which caught the drippings, or gutterings, from barrels. Which would connect it to gutter (v.).
gutless (adj.): "cowardly," 1900, from gut (n.) in the figurative "spirit" sense (see guts) + -less. Literal sense "disemboweled" is from c. 1600. Related: Gutlessly; gutlessness.
guts (n.): "spirit, courage," 1893, figurative plural of gut (n.). The idea of the bowels as the seat of the spirit goes back to at least mid-14c. (compare bowel).
gutsy (adj.): "tough, plucky," 1893, from guts + -y (2). Earlier it meant "greedy" (1803).
gutta-percha (n.): 1845, from Malay getah percha, literally "the gum of percha," the name of the tree; the form of the word was influenced by Latin gutta "drop." As the name of the tree itself, from 1860.
gutter (n.): late 13c., "watercourse, water drainage channel along the side of a street," from Anglo-French gotere, Old French guitere, goutiere "gutter, spout" of water (12c., Modern French gouttière), from goute "a drop," from Latin gutta "a drop" (see gout). Meaning "furrow made by running water" is from 1580s. Meaning "trough under the eaves of a roof to carry off rainwater" is from mid-14c. Figurative sense of "low, profane" is from 1818. In printers' slang, from 1841.
gutter (v.): late 14c., "to make or run in channels" (transitive), from gutter (n.). Intransitive use, in reference to candles (1706) it is from the channel that forms as the molten wax flows off. Related: Guttered; guttering.
guttersnipe (n.): also gutter-snipe, 1857, from gutter (n.) + snipe (n.); originally Wall Street slang for "streetcorner broker," attested later (1869) as "street urchin," also "one who gathers rags and paper from gutters." As a name for the common snipe, it dates from 1874 but is perhaps earlier.
guttural (adj.): "pertaining to the throat," 1590s, from Middle French guttural, from Latin guttur "throat, gullet," perhaps expressive of throat-noises. "Note that gula, glut- and gurgulio also refer to the 'throat' and 'swallowing', and also contain g(l)u-. Guttur may belong to this same family, which has no PIE etymology" [de Vaan]. The noun, in linguistics, is from 1690s.
guv (n.): 1890, shortening of guvner, casual British pronunciation of governor as a title of respect.
guy (n.1): "small rope, chain, wire," 1620s, nautical; earlier "leader" (mid-14c.), from Old French guie "a guide," also "a crane, derrick," from guier (see guide (v.)); or from a related word in North Sea Germanic.
guy (n.2): "fellow," 1847, American English; earlier, in British English (1836) "grotesquely or poorly dressed person," originally (1806) "effigy of Guy Fawkes," leader of the Gunpowder Plot to blow up British king and Parliament (Nov. 5, 1605). The effigies were paraded through the streets by children on the anniversary of the conspiracy. The male proper name is from French, related to Italian Guido.
Guyana: from a native word perhaps meaning "respectable." Related: Guyanese.
guyot (n.): "flat-topped submarine mountain," 1946, named for Swiss geographer/geologist Arnold Guyot (1807-1884).
guzzle (v.): 1570s, "swallow liquid greedily" (intransitive), 1580s in transitive sense, probably related to Old French gosillier "to go down the gullet; to vomit, chatter, talk," from gosier (13c.) "jaws, throat, gullet." Or imitative of the sound of drinking greedily. Related: Guzzled; guzzling.
guzzle (n.): 1590s, "a drain," from guzzle (v.). From 1704 as "liquor," 1836 as "bout of heavy drinking."
guzzler (n.): 1704, agent noun from guzzle (v.).
Gwen: fem. proper name, typically short for Gwendolyn.
Gwendolyn: fem. proper name; the first element is Breton gwenn "white" (source also of Welsh gwyn, Old Irish find, Gaelic fionn, Gaulish vindo- "white, shining," literally "visible"), from nasalized form of PIE root *weid- "to see, know" (see vision).
gybe (v.2): alternative spelling of jibe.
gybe (v.1): "swing from one side to the other," nautical, 1690s, probably from older Dutch gijben, related to German gieben, of uncertain origin.
gym (n.): short for gymnasium, 1871, U.S. student slang.
gymkhana (n.): 1854, Anglo-Indian, said to be from Hindustani gend-khana, literally "ball house," said in Yule & Burnell's 1886 glossary of Anglo-Indian words to be "the name usually given in Hindu to an English racket-court." The second element is from Middle Persian khan "house," from Iranian *ahanam "seat," from PIE *es- "to sit." Altered in English by influence of gymnasium, etc.
gymnasium (n.): 1590s, "place of exercise," from Latin gymnasium "school for gymnastics," from Greek gymnasion "public place where athletic exercises are practiced; gymnastics school," in plural, "bodily exercises," from gymnazein "to exercise or train," literally or figuratively, literally "to train naked," from gymnos "naked," from a metathesis of PIE *nogw-mo-, suffixed form of *nogw- "naked" (see naked).

A feature of all ancient Greek communities, at first it was merely an open space, later with extensive facilities and including training for the mind as well as the body. Hence its use in German from 15c. as a name for "high school" (more or less paralleling a sense also in Latin); in English it has remained purely athletic. For the "continental high school sense," English in 19c. sometimes used gymnastical as an adjective, gymnasiast for a student.
gymnast (n.): 1590s, "one who is expert in gymnastics," a back-formation from gymnastic. Greek gymnastes was "a trainer of professional athletes."
gymnastic (adj.): 1570s, "pertaining to athletic exercise," from Latin gymnasticus, from Greek gynmastikos "fond of or skilled in bodily exercise," from gymnazein "to exercise or train" (see gymnasium).
gymnastics (n.): 1650s, from gymnastic; also see -ics.
gymno-: before vowels gymn-, word-forming element meaning "naked, stripped, bare," from comb. form of Greek gymnos "naked, unclad; bare, mere," from a metathesis of PIE *nogw-mo-, suffixed form of *nogw- "naked" (see naked).
gymnosophist (n.): c. 1400, from Greek gymnosophistai "the naked philosophers," from gymnos "naked" (see naked) + sophistes "wise man" (see sophist). Ancient Hindu holy men whose self-denial extended to clothes; they were known to the later Greeks through the reports of Alexander the Great's soldiers.
gymnosperm (n.): 1836, from French gymnosperme and Modern Latin gymnospermae (plural, 17c.), literally "naked seed" (i.e., not enclosed in an ovary), from gymno- "naked" + sperma "seed" (see sprout (v.)). Related: Gymnospermous.
gynaecolatry (n.): "worship of women," 1888; see gyneco- + -latry. Related: Gynaecolater; gynaecolatrous.
gynarchy (n.): "government by women or a woman," 1570s, from Greek gyne "woman, wife," from PIE *gwen- "woman" (see queen) + -arkhe "rule" (see archon). Synonymous gynaecocracy (from Greek gynaikokratia) and gyneocracy are attested from 1610s; gynocracy is from 1728.
gyneco-: also gynaeco-, before a vowel gynec-, word-forming element meaning "woman, female," from Latinized form of Greek gynaiko-, comb. form of gyne "woman, female," from PIE root *gwen- "woman" (see queen).
gynecological (adj.): also gynaecological, 1858, from gynecology + -ical. Related: Gynecologically.
gynecologist (n.): also gynaecologist, 1851, from gynecology + -ist.
gynecology (n.): also gynaecology, "science of women's health and of the diseases peculiar to women," 1847, from French gynécologie, from Latinized form of Greek gynaiko-, comb. form of gyne "woman, female," from PIE *gwen- "woman" (see queen). Second element is from French -logie "study of," from Greek (see -logy). Another word for it was gyniatrics.
gynecomastia (n.): also gynaecomastia, gynecomasty, "condition of a man having breasts like a woman's," 1881, from gyneco- "woman, female" + Latinized form of Greek mazos "breast," variant of mastos (see masto-) + abstract noun ending -ia.
gyno-: word-forming element especially in modern medical and botanical words equivalent to gyneco-.
gyp (v.): also gip, "to cheat, swindle," 1889, American English, traditionally derived from Gypsy (n.). Gyp/gip/jip is attested from 1794 as university slang for a servant that waited on students in their halls. This is said to have been especially a Cambridge word, and a story told there derived it from Greek gyps "vulture," in reference to thievish habits of the servants.

As a noun, "fraudulent action, a cheat," by 1914. Gypsy's abbreviated form Gip, Gyp is attested from 1840. Gypping or gipping was a term late 19c. among horse dealers for tricks such as painting the animal's gray hairs brown, puffing the gums, etc. Related: Gypped.
gypsophila (n.): genus of the pink family, 1771, from Modern Latin (Linnaeus), from Greek gypsos "chalk, gypsum" (see gypsum) + philein "to love" (see philo-).
gypsum (n.): substance (hydrated calcium sulphate) used in making plaster, late 14c., from Latin gypsum, from Greek gypsos "chalk," according to Klein, a word perhaps of Semitic origin (compare Arabic jibs, Hebrew gephes "plaster").
Gypsy (n.): also gipsy, c. 1600, alteration of gypcian, a worn-down Middle English dialectal form of egypcien "Egyptian," from the supposed origin of the people. As an adjective, from 1620s. Compare British gippy (1889) a modern shortened colloquial form of Egyptian.

Cognate with Spanish Gitano and close in sense to Turkish and Arabic Kipti "gypsy," literally "Coptic;" but in Middle French they were Bohémien (see bohemian), and in Spanish also Flamenco "from Flanders." "The gipsies seem doomed to be associated with countries with which they have nothing to do" [Weekley]. Zingari, the Italian and German name, is of unknown origin. Romany is from the people's own language, a plural adjective form of rom "man." Gipsy was the preferred spelling in England. The name is also in extended use applied to "a person exhibiting any of the qualities attributed to Gipsies, as darkness of complexion, trickery in trade, arts of cajolery, and, especially as applied to a young woman, playful freedom or innocent roguishness of action or manner" [Century Dictionary]. As an adjective from 1620s with a sense "unconventional; outdoor."
gyrate (v.): "move in a circle or spiral," 1763 (implied in gyrated), back-formation from gyration. Related: Gyrated; gyrating.
gyration (n.): 1610s, noun of action from gyre (v.).
gyre (n.): 1560s, "a circular motion," from Latin gyrus "circle, circular course, round, ring," from Greek gyros "a circle, ring," related to gyrós "rounded," perhaps from PIE root *geu- "to bend, curve" (source also of Armenian kor "crooked," Lithuanian gurnas "hip, ankle, bone," Norwegian kaure "a curly lock of hair"). The noun is attested in Middle English only in reference to ship's tackle (early 15c.).
gyre (v.): mid-15c., "turn (something) away (from something else); rotate" (transitive), "cause to revolve;" also "go in a circle, turn round" (intransitive), from Old French girer and directly from Latin gyrare, verb derived from gyrus "circle, circular course, round, ring" (see gyre (n.)). Related: Gyred; gyring.
gyrfalcon (n.): large falcon used in hawking, also gerfalcon, c. 1200, partly Englished from Old French girfauc "large northern falcon," probably from a Frankish compound with Latin falco "hawk" (see falcon) + first element meaning "vulture," from Proto-Germanic *ger (source of Old High German gir "vulture"). Folk etymology since the Middle Ages has connected it with Latin gyrus (see gyre (n.)) in reference to "circling" in the air.
gyro (n.): sandwich made from roasted lamb, 1971, originally the meat itself, as roasted on a rotating spit, from Modern Greek gyros "a circle" (see gyre (n.)). Mistaken in English for a plural and shorn of its -s.
gyro-: word-forming element meaning "gyrating" or "gyroscope," from comb. form of Greek gyros "a ring, circle" (see gyre (n.)).
gyrocopter (n.): 1915, from gyro- + ending as in helicopter.