Online Etymology Dictionary

geratology (n.): "study of decadence," 1884, from Greek geras (genitive geratos) "old age" (see geriatric) + -logy.
gerbera: 1880, from Modern Latin (1737), named for German naturalist Traugott Gerber (1710-1743).
gerbil (n.): 1849, from French gerbille, from Modern Latin Gerbillus, the genus name, from gerbo, from Arabic yarbu. Earlier English form, jarbuah (1660s), was directly from Arabic.
geriatric (adj.): 1909, formed in English from Greek geras, geros "old age" (from PIE root *gere- "to grow old" (see gerontology) + iatrikos "of a physician," from iatros (see -iatric).
geriatrics (n.): coined 1909 by Austrian-born doctor Ignatz L. Nascher (1863-1944) in "New York Medical Journal" on the model of pediatrics (cf. -ics), from the same elements found in geriatric (q.v.). The correct formation would be gerontiatrics.
germ (n.): mid-15c., "bud, sprout;" 1640s, "rudiment of a new organism in an existing one," from Middle French germe "germ (of egg); bud, seed, fruit; offering," from Latin germen (genitive germinis) "sprout, bud," perhaps from PIE root *gen- "to beget, bear" (see genus). The older sense is preserved in wheat germ and germ of an idea; sense of "seed of a disease" first recorded 1803; that of "harmful microorganism" dates from 1871. Germ warfare recorded from 1920.
german (adj.): "of the same parents or grandparents," c.1300, from Old French germain "closely related" (12c.), from Latin germanus "full, own (of brothers and sisters); one's own brother; genuine, real," related to germen (genitive germinis) "sprout, bud," dissimilated from PIE *gen(e)-men-, from root *gene- "to give birth, beget" (see genus). Your cousin-german (also first cousin) is the son or daughter of an uncle or aunt; your children and your first cousin's are second cousins to one another; to you, your first cousin's children are first cousin once removed.
German (n.): "Teuton, member of the Germanic tribes," 1520s (plural Germayns attested from late 14c.), from Latin Germanus, first attested in writings of Julius Caesar, who used Germani to designate a group of tribes in northeastern Gaul, origin unknown, probably the name of an individual tribe. It is perhaps of Gaulish (Celtic) origin, perhaps originally meaning "noisy" (cf. Old Irish garim "to shout") or "neighbor" (cf. Old Irish gair "neighbor"). The earlier English word was Almain (early 14c.) or Dutch.
Þe empere passede from þe Grees to þe Frenschemen and to þe Germans, þat beeþ Almayns. [John of Trevisa, translation of Higdon's Polychronicon, 1387]
Their name for themselves was the root word of modern German Deutsch (see Dutch). Roman writers also used Teutoni as a German tribal name, and Latin writers after about 875 commonly refer to the German language as teutonicus. See also Alemanni and Teutonic. As an adjective, from 1550s. The German shepherd (dog) (1922) translates German deutscher Schäferhund. German Ocean as an old name for the North Sea translates Ptolemy. German measles attested by 1856.
germane (adj.): mid-14c., "having the same parents," derived from german (adj.); cf. human/humane, urban/urbane. Main modern sense of "closely connected, relevant" (c.1600) derives from use in "Hamlet" Act V, Scene ii: "The phrase would bee more Germaine to the matter: If we could carry Cannon by our sides," which is a figurative use of the word in the now-obsolete sense of "closely related, akin" (late 15c.) in reference to things, not persons.
Germanic (adj.): 1630s, "of Germany or Germans," from German (n.) + -ic. As the name of a language family, 1892, replacing earlier Teutonic. Germanical is attested from 1550s.
Germany: c.1300, from Latin Germania, a Roman designation (see German (n.)). In Middle English the place also was called Almaine (early 14c.).
germicide (n.): 1880, from germ + -cide.
germinal (adj.): 1808, from Modern Latin germinalis "in the germ," from Latin germen (genitive germinis) "sprout, bud, sprig, offshoot" (see germ) + -al (1).
germinate (v.): c.1600, probably a back-formation from germination. Earlier germynen (mid-15c.) was from Latin germinare. Figurative use from 1640s. Related: Germinated; germinating.
germination (n.): mid-15c., from Latin germinationem (nominative germinatio) "sprouting forth, budding," noun of action from past participle stem of germinare "to sprout, put forth shoots," from germen (genitive germinis) "a sprout or bud" (see germ).
germy (adj.): 1912, from germ + -y (2).
Geronimo: cry made in jumping, apparently from the story of the Apache leader Geronimo making a daring leap to escape U.S. cavalry pursuers at Medicine Bluffs, Oklahoma (and supposedly shouting his name in defiance as he did). Adopted as battle cry by 82nd Airborne U.S. paratroopers in World War II, who perhaps had seen it in the 1939 Paramount Studios movie "Geronimo." The name is the Italian and Spanish form of Jerome, from Greek Hieronomos, literally "sacred name."
gerontocracy (n.): rule by old men, 1830, from Greek geront-, from geron "old man" (see gerontology) + kratia "rule" (see -cracy). Related: Gerontocratic.
gerontologist (n.): 1941, from gerontology + -ist.
gerontology (n.): 1903, coined in English from Greek geron (genitive gerontos) "old man," from PIE root *gere- "to become ripe, grow old" (cf. Sanskrit jara "old age," jarati "makes frail, causes to age;" Avestan zaurvan "old age;" Ossetic zarond "old man;" Armenian cer "old, old man").
gerrymander: 1812 as both a noun and verb, American English, from Elbridge Gerry + (sala)mander. Gerry, governor of Massachusetts, was lampooned when his party redistricted the state in a blatant bid to preserve an Antifederalist majority. One Essex County district resembled a salamander, and a newspaper editor dubbed it Gerrymander. Related: Gerrymandered; gerrymandering.
Gertrude: fem. proper name, from French, from Old High German Geretrudis, from ger "spear" + trut "beloved, dear."
gerund (n.): 1510s, from Late Latin gerundium, from Old Latin gerundum "to be carried out," gerundive of gerere "to bear, carry." In Latin, a verbal noun used for all cases of the infinitive but the nominative; applied in English to verbal nouns in -ing.
gerundive (adj.): early 15c., from Latin gerundivus (modus), from gerundium (see gerund).
Gervais: masc. proper name, French Gervais, from Old High German Gervas, literally "serving with one's spear," from ger "spear" + Celtic base *vas- "servant."
gesellschaft (n.): 1887, "social relationship based on duty to society or an organization," from German Gesellschaft, from geselle "companion" + -schaft "-ship."
gesso: plaster of Paris, 1590s, from Italian gesso, from Latin gypsum (see gypsum).
gest (n.): "famous deed, exploit; story, romance," c.1300, from Old French geste "action, exploit, romance, history (of celebrated people or actions)," from Latin gesta "actions, exploits, deeds, achievements," neuter plural of gestus, past participle of gerere "to carry on, wage, perform," of unknown origin. Cf. jest.
Gestalt: 1922, from German Gestaltqualität (1890, introduced by German philosopher Christian von Ehrenfels, 1859-1932), from German gestalt "shape, form, figure, configuration, appearance," abstracted from ungestalt "deformity," noun use of adj. ungestalt "misshapen," from gestalt, obsolete past participle of stellen "to place, arrange" (see stall (n.1)). As a school of psychology, it was founded c.1912 by M Wertheimer, K. Koffka, W. Köhler.
Gestapo: Nazi secret state police, 1934, from German Gestapo, contracted from "Geheime Staats-polizei," literally "secret state police," set up by Hermann Göring in Prussia in 1933, extended to all Germany in January 1934.
gestate (v.): 1866, back-formation from gestation. Related: Gestated; gestating.
gestation (n.): 1530s, "riding on horseback, etc., as a form of exercise," from Latin gestationem (nominative gestatio) "a carrying," noun of action from gestare "bear, carry, gestate," frequentative of gerere (past participle gestus) "to bear, carry, bring forth" (see gest). Meaning "action or process of carrying young in the womb" is from 1610s.
gestational (adj.): 1970, from gestation + -al (1). Related: Gestationally.
gesticulate (v.): c.1600, from Latin gesticulatus, past participle of gesticulari "to gesture, mimic," from gesticulus "a mimicking gesture," diminutive of gestus "gesture, carriage, posture" (see gest). Related: Gesticulated; gesticulating.
gesticulation (n.): early 15c., from Latin gesticulationem (nominative gesticulatio), noun of action from past participle stem of gesticulari "to gesture, mimic," from gesticulus "a mimicking gesture," diminutive of gestus (see gest).
gesticulator (n.): 1690s, agent noun in Latin form from gesticulate.
gestural (adj.): 1610s, from gesture + -al (1). Related: Gesturally.
gesture (n.): early 15c., "manner of carrying the body," from Medieval Latin gestura "bearing, behavior," from Latin gestus "gesture, carriage, posture" (see gest). Restricted sense of "a movement of the body or a part of it" is from 1550s; figurative sense of "action undertaken in good will to express feeling" is from 1916.
gesture (v.): 1540s, from gesture (n.). Related: Gestured; gesturing.
gesundheit: 1914, from German Gesundheit, literally "health!" Also in toast auf ihre Gesundheit "to your health" (see sound (adj.)). Lithuanian aciu, echoic of the sound of a sneeze, has come to mean "good luck, God bless you." See also God.
get (v.): c.1200, from Old Norse geta "to obtain, reach; to beget; to guess right" (past tense gatum, past participle getenn), from Proto-Germanic *getan (cf. Old Swedish gissa "to guess," literally "to try to get"), from PIE root *ghend- "seize, take" (cf. Greek khandanein "to hold, contain," Lithuanian godetis "be eager," second element in Latin prehendere "to grasp, seize," Welsh gannu "to hold, contain," Old Church Slavonic gadati "to guess, suppose"). Meaning "to seize mentally, grasp" is from 1892.

Old English, as well as Dutch and Frisian, had the root only in compounds (e.g. begietan "to beget," see beget; forgietan "to forget," see forget). Vestiges of Old English cognate *gietan remain obliquely in past participle gotten and original past tense gat. The word and phrases built on it take up 29 columns in the OED 2nd edition. Related: Getting.

Get wind of "become acquainted with" is from 1840, from earlier to get wind "to get out, become known" (1722). Get out, as a command to go away, is from 1711. Get-rich-quick (adj.) attested from 1904, first in O. Henry. To get out of hand originally (1765) meant "to advance beyond the need for guidance;" sense of "to break free, run wild" is from 1892, from horses. To get on (someone's) nerves is attested by 1970.
get (n.): early 14c., "offspring," from get (v.). Meaning "what is got, booty" is from 14c.
get back: c.1600 (intransitive) "to return;" 1808 (transitive) "to recover" (something); meaning "retaliate" is attested by 1888.
get off: "escape," c.1600. Sexual sense attested by 1973.
get on: "to put on," 1590s. Meaning "prosper" is from 1785; "to advance, make progress" is from 1798. That of "be friendly" (with) is attested by 1816.
get over: "overcome," 1680s; "recover from," 1712; "have done with," 1813.
get together: c.1400, "collect, gather;" meaning "to meet, to assemble" is from 1690s; "to organize" (oneself), 1962.
get up: "rise," mid-14c. As a noun, "equipment or costume," from 1847; also get-up, getup. Meaning "initiative, energy" recorded from 1841.
get-out: to indicate a high degree of something, attested from 1838.
get-together (n.): 1911, from get + together.