Online Etymology Dictionary

good (adj.): Old English god (with a long "o") "virtuous; desirable; valid; considerable," probably originally "having the right or desirable quality," from Proto-Germanic *gothaz (cf. Old Norse goðr, Dutch goed, Old High German guot, German gut, Gothic goþs), originally "fit, adequate, belonging together," from PIE root *ghedh- "to unite, be associated, suitable" (cf. Old Church Slavonic godu "pleasing time," Russian godnyi "fit, suitable," Old English gædrian "to gather, to take up together"). As an expression of satisfaction, from early 15c.; of children, "well-behaved," by 1690s.

Irregular comparatives (better, best) reflect a widespread pattern, cf. Latin bonus, melior, optimus. Good-for-nothing is from 1711. Good looking is attested from 1780 (good looks by c.1800). Good sport, of persons, is from 1906; good to go is attested from 1989. The good book "the Bible" attested from 1801, originally in missionary literature describing the language of conversion efforts in American Indian tribes.
Why then, can one desire too much of a good thing. ["As You Like It"]
good (n.): Old English gōd "that which is good, goodness; advantage, benefit; gift; virtue; property;" from good (adj.).
good day: salutation, late 14c., short for have a good day (c.1200). Good morning is c.1400, gode morwene. Good night, also goodnight, is late 14c.; as an exclamation of surprise, from 1893.
Good Friday: late 13c., from good in Middle English sense of "holy," also especially of holy days or seasons observed by the church (early 15c.); the word also was applied to Christmas and Shrove Tuesday.
good will: Old English godes willan "virtuous, pious, upright," also "state of wishing well to another." One-word form goodwill (18c.) is used especially in commercial senses.
good-bye: also goodbye, good bye, good-by, 1590s, from godbwye (1570s), itself a contraction of God be with ye (late 14c.), influenced by good day, good evening, etc.
good-natured (adj.): 1570s, from good (adj.) + nature. Good nature "pleasing or kind disposition" is from mid-15c. Related: Good-naturedly.
good-neighbor (adj.): also (chiefly British English) good-neighbour, adjectival phrase, in reference to U.S. foreign policy, especially in Latin America, 1928, originally in Herbert Hoover. The good neighbours is Scottish euphemism for "the fairies" (1580s).
good-time (adj.): 1928, from good (adj.) + time. Expression to have a good time "enjoy oneself" attested from 1822; earlier have a good time of it (1771). To make good time "go fast" is from 1838.
goodly: Old English godlic "goodly, excellent; comely fair;" see good (adj.) + -ly (1).
goodness (n.): Old English godnes "goodness, virtue, kindliness;" see good (adj.) + -ness. In exclamations from 1610s, first recorded being for goodnesse sake, i.e. "as you trust in the goodness of God."
goods (n.): "property," late 13c., from plural of good (n.), which had the same sense in Old English. Meaning "saleable commodities" is mid-15c.; colloquial sense of "stolen articles" is from 1900; hence figurative use, "evidence of guilt."
goody (n.): also goodie, "something tasty," 1745, from good (adj.) + -y (2); adj. use for "sentimentally proper" is 1830 (especially in reduplicated form goody-goody, 1871). As an exclamation of pleasure, by 1796. Goody also used since 1550s as a shortened form of goodwife, a term of civility applied to a married woman in humble life; hence Goody Two-shoes, name of heroine in 1760s children's story who exulted upon acquiring a second shoe.
gooey (adj.): 1893, American English slang, from goo + -y (2). The first element perhaps somehow imitative, or shortened from burgoo (1787) "thick porridge."
goof (n.): 1916, American English, "stupid person," perhaps a variant of English dialect goff "foolish clown" (1869), from 16c. goffe, probably from Middle French goffe "awkward, stupid," of uncertain origin. Or English goffe may be from Middle English goffen "speak in a frivolous manner," possibly from Old English gegaf "buffoonery," and gaffetung "scolding." Sense of "a blunder" is c.1954, probably influenced by gaffe.
goof (v.): "waste time," 1932; "make a mistake," 1941, from goof (n.). Goof off "loaf" is also from 1941. Related: Goofed; goofing.
goofball (n.): "narcotic," 1938, from goof + ball (n.1); as an intensive of goof (n.), it dates from 1959.
goofiness (n.): 1929, from goofy + -ness.
goofy (adj.): 1921, from goof + -y (2). The Disney character of that name began life c.1929 as Dippy Dawg.
google (v.): "to search (something) on the Google search engine," 2000 (do a google on was used by 1999). The domain google.com was registered in 1997. A verb google was an early 20c. cricket term in reference to a type of breaking ball.
googly: as a noun, a cricket term, 1903, of unknown origin. As an adjective, of eyes, 1901.
googol (n.): 1940, in "Mathematics and the Imagination," a layman's book on mathematics written by U.S. mathematicians Edward Kasner (1878-1955) and James R. Newman, the word supposedly coined a year or two before by Kasner's 9- (or 8-) year-old nephew (unnamed in the book's account of the event), when asked for a name for an enormous number. Perhaps influenced by comic strip character Barney Google. Googolplex coined at the same time, in the same way.
gook (n.): 1899, U.S. military slang for "Filipino" during the insurrection there, probably from a native word, or imitative of the babbling sound of their language to American ears (cf. barbarian). The term goo-goo eyes "soft, seductive eyes" was in vogue c.1900 and may have contributed to this somehow. Extended over time to "Nicaraguan," "any Pacific Islander" (World War II), "Korean" (1950s), "Vietnamese" and "any Asian" (1960s).
goombah (n.): by 1984, from dialectal pronunciation of Italian compare "companion, godfather" (cf. compadre).
goon (n.): 1921, "stupid person," from gony "simpleton" (1580s), of unknown origin, but applied by sailors to the albatross and similar big, clumsy birds (1839); sense of "hired thug" first recorded 1938 (in reference to union "beef squads" used to cow strikers in the Pacific northwest), probably from Alice the Goon, slow-witted and muscular (but gentle-natured) character in "Thimble Theater" comic strip (starring Popeye) by E.C. Segar (1894-1938). She also was the inspiration for British comedian Spike Milligan's "The Goon Show." What are now "juvenile delinquents" were in the 1940s sometimes called goonlets.
goose (n.): "a large waterfowl proverbially noted, I know not why, for foolishness" [Johnson], Old English gos, from Proto-Germanic *gans- "goose" (cf. Old Frisian gos, Old Norse gas, Old High German gans, German Gans "goose"), from PIE *ghans- (cf. Sanskrit hamsah (masc.), hansi (fem.), "goose, swan;" Greek khen; Latin anser; Polish gęś "goose;" Lithuanian zasis "goose;" Old Irish geiss "swan"), probably imitative of its honking.

Spanish ganso "goose" is from a Germanic source. Loss of "n" sound is normal before "s." Plural form geese is an example of i-mutation.

Meaning "simpleton" is from 1540s. To cook one's goose first attested 1845, of unknown origin; attempts to connect it to Swedish history and Greek fables have been unconvincing. Goose egg "zero" first attested 1866 in baseball slang. The goose that laid the golden egg is from Aesop.
goose (v.): "jab in the rear," c.1880, from goose (n.), possibly from resemblance of the upturned thumb to a goose's beak. Related: Goosed; goosing. In 19c. theatrical slang, to be goosed meant "to be hissed" (by 1818).
goose step (n.): 1806, originally was a military drill to teach balance; "to stand on each leg alternately and swing the other back and forth" (which, presumably, reminded someone of a goose's way of walking); in reference to "marching without bending the knees" (as in Nazi military reviews) it apparently is first recorded 1916. As a verb by 1854.
gooseberry (n.): 1530s, perhaps from German Krausebeere or Kräuselbeere, related to Middle Dutch croesel "gooseberry," and to German kraus "crispy, curly" [Klein, etc.]. Under this theory, gooseberry would be folk etymology. But OED editors find no reason to prefer this to a literal reading, because "the grounds on which plants and fruits have received names associating them with animals are so commonly inexplicable, that the want of appropriateness in the meaning affords no sufficient ground for assuming that the word is an etymological corruption."
goosebumps (n.): also goose bumps, 1919, from goose (n.) + bump (n.). Earlier in the same sense was goose flesh (c.1810) and goose skin (1785).
GOP: "U.S. Republican Party," 1884, an abbreviation of Grand Old Party. The Republicans were so called from 1876; the Democratic Party also was referred to occasionally as grand old party, with lower-case letters, in 1870s-80s and had a greater claim to the title.
gopher (n.): 1812, American English, perhaps an Anglicization of Louisiana French gaufre "honeycomb, waffle," said to have been used by French settlers in reference to small mammals on analogy of the structure of their burrows, from Old French gaufre, of Frankish origin. The rodent was the nickname of people from Arkansas (1845) and later Minnesota (1872). The gopherwood tree of the Bible (used by Noah to make the ark, Gen. vi:14) is unrelated; it is from Hebrew gofer, perhaps meaning the cypress.
Gordian knot: 1560s, tied by Gordius, king of Phrygia in Asia Minor, who predicted the one to loosen it would rule Asia. Instead, Alexander the Great cut the Gordian knot with his sword; hence the extended sense (1570s in English) "solve a difficult problem in a quick, dramatic way."
gore (n.2): "triangular piece of ground," Old English gara, related to gar "spear" (see gar), on the notion of "triangularity." Hence also meanings "front of a skirt" (mid-13c.), and "triangular piece of cloth" (early 14c.).
gore (n.1): Old English gor "dirt, dung, filth, shit," a Germanic word (cf. Middle Dutch goor "filth, mud;" Old Norse gor "cud;" Old High German gor "animal dung"), of uncertain origin. Sense of "clotted blood" (especially shed in battle) developed by 1560s.
gore (v.): c.1400, from Scottish gorren "to pierce, stab," origin unknown, perhaps related to Old English gar "spear" (see gar, also gore (n.2) "triangular piece of ground"). Related: Gored; goring.
gorge (n.): mid-14c., "throat," from Old French gorge "throat, bosom," from Late Latin gurges "gullet, throat, jaws," of uncertain origin, probably related to Latin gurgulio "gullet, windpipe," from PIE *gwere- "to swallow." Transferred sense of "deep, narrow valley" was in Old French.
gorge (v.): "eat greedily," c.1300, from Old French gorger, from gorge (see gorge (n.)). Related: Gorged; gorging.
gorgeous (adj.): late 15c., "splendid, showy" (of clothing), from Middle French gorgias "elegant, fashionable," of unknown origin; perhaps literally "necklace" (and thus "fond of jewelry"), from Old French gorge "bosom, throat," also "something adorning the throat." A connection to the Greek proper name Gorgias (supposedly in reference to a notorious sophist) also has been proposed. Related: Gorgeousness.
gorgeously (adv.): 1530s, from gorgeous + -ly (2).
gorget (n.): "armor for the throat," late 15c., from Old French gorgete, diminutive of gorge "throat" (see gorge (n.)).
Gorgon: late 14c., any of the three hideous sisters in Greek legend, whose look turned beholders to stone (Madusa was one of them), from Greek Gorgo (plural Gorgones), from gorgos "terrible," of unknown origin. Transferred sense of "terrifyingly ugly person" is from 1520s.
gorgonzola: type of blue cheese, 1878, named for Gorgonzola, village near Milan where it first was made.
gorilla (n.): 1847, applied to the apes (Troglodytes gorills) by U.S. missionary Thomas Savage, from Greek gorillai, plural of name given to wild, hairy people in a Greek translation of Carthaginian navigator Hanno's account of his voyage along the N.W. coast of Africa, c.500 B.C.E. Allegedly an African word.
In its inmost recess was an island similar to that formerly described, which contained in like manner a lake with another island, inhabited by a rude description of people. The females were much more numerous than the males, and had rough skins: our interpreters called them Gorillae. We pursued but could take none of the males; they all escaped to the top of precipices, which they mounted with ease, and threw down stones; we took three of the females, but they made such violent struggles, biting and tearing their captors, that we killed them, and stripped off the skins, which we carried to Carthage: being out of provisions we could go no further. [Hanno, "Periplus"]
Of persons perceived as being gorilla-like, from 1884.
gorm (n.): "fool," 1912, perhaps from gormless.
gormandize (v.): 1540s, from gourmand + -ize.
gormless (adj.): c.1746, "wanting sense," a British dialectal word, from gome "notice, understanding" (c.1200), from Old Norse gaumr "care, heed," of unknown origin; + -less.
gorse (n.): Old English gors "gorse, furze," from Proto-Germanic *gorst- (cf. Old Saxon, Old High German gersta, Middle Dutch gherste, Dutch gerst, German gerste "barley"), from PIE *ghers- "to bristle" (cf. Latin hordeum "barley;" see horror).
gory (adj.): "blood-soaked," late 15c., from gore (n.) + -y (2).
gosh: 1757, altered pronunciation of God. Probably from by gosse (mid-16c.).