Online Etymology Dictionary

upturn (n.): 1868, "upturned part," from up + turn. Meaning "improvement" (especially in economics) is from 1930.
upward: Old English upweard, upweardes; see up + -ward. Cf. Middle Low German upwart, Middle Dutch opwaert, Middle High German ufwart. Phrase upward mobility first recorded 1949; mainly restricted to sociologists' jargon until 1960s.
upwelling: 1854 (adj.), 1868 (n.), from up + present participle of well (v.).
upwind (adj.): 1838, from up- + wind (n.1). Originally a nautical term.
ur-: prefix meaning "original, earliest, primitive," from German; at first only in words borrowed from German (cf. ursprache "hypothetical primitive language"); since mid-20c. a living prefix in English. Cf. also Urschleim under protoplasm and Urquell under Pilsner.
uracil: coined in German, 1885, perhaps from urea + German Acetsäure "acetic acid" + chemical suffix -il.
Ural: mountain range between Europe and Asia (the river is named for the mountains), of uncertain origin. Perhaps from Vogul urala "mountain peak" or from Tatar ural "boundary."
uranium (n.): rare metallic element, 1797, named 1789 in Modern Latin by its discoverer, German chemist and mineralogist Martin Heinrich Klaproth (1743-1817), for the recently found planet Uranus (q.v.).
Uranus: first planet discovered that was not known in ancient times, named for the god of Heaven, husband of Gaia, the Earth, from Latin Uranus, from Greek Ouranos literally "heaven," in Greek cosmology, the god who personifies the heavens, father of the titans. Cf. Urania, name of the Muse of astronomy, from Greek Ourania, fem. of ouranios, literally "heavenly."

The planet was discovered and identified as such in 1781 by Sir William Herschel (it had been observed before, but mistaken for a star, e.g. in 1690 when John Flamsteed cataloged it as 34 Tauri); Herschel proposed calling it Georgium Sidus, literally "George's Star," in honour of his patron, King George III of England.
I cannot but wish to take this opportunity of expressing my sense of gratitude, by giving the name of Georgium Sidus ... to a star which (with respect to us) first began to shine under His auspicious reign. [Sir William Herschel, 1783]
The planet was known in English in 1780s as the Georgian Planet; French astronomers began calling Herschel, and ultimately German astronomer Johann Bode proposed Uranus as in conformity with other planet names. However, the name didn't come into common usage until c.1850.
urban (adj.): "characteristic of city life," 1610s (but rare before 1830s), from Latin urbanus "of or pertaining to a city or city life," as a noun, "city dweller," from urbs (genitive urbis) "city," of unknown origin. The word gradually emerged in this sense as urbane became restricted to manners and styles of expression. In late 20c. American English gradually acquiring a suggestion of "African-American." Urban renewal, euphemistic for "slum clearance," is attested from 1955, American English. Urban sprawl recorded by 1958. Urban legend attested by 1980.
urbane (adj.): 1530s, "of or relating to cities or towns," from Middle French urbain (14c.), from Latin urbanus "belonging to a city," also "citified, elegant" (see urban). The meaning "having the manners of townspeople, courteous, refined" is first attested 1620s. Urbanity in this sense is recorded from 1530s. For sense connection, cf. human/humane.
urbanisation (n.): chiefly British English spelling of urbanization. For spelling, see -ize.
urbanism (n.): 1885, from urban + -ism.
urbanite (n.): 1897, from urban + -ite.
urbanity (n.): 1530s, from French urbanité (14c.) or directly from Latin urbanitas, from urbanus (see urban).
urbanization (n.): 1888, noun of action from urbanize.
urbanize (v.): 1640s, "to make more civil;" 1884 "to make into a city," from urban + -ize; in the latter sense from French urbaniser (1873). Related: Urbanized; urbanizing.
urchin (n.): late 13c., yrichon "hedgehog," from Old North French *irechon (cf. Picard irechon, Walloon ireson, Hainaut hirchon), from Old French herichun "hedgehog" (Modern French hérisson), formed with diminutive suffix -on + Vulgar Latin *hericionem, from Latin ericius "hedgehog," from PIE root *gher- "to bristle" (cf. Greek kheros "hedgehog;" see horror).

Still used for "hedgehog" in non-standard speech in Cumbria, Yorkshire, Shropshire. Applied throughout 16c. to people whose appearance or behavior suggested hedgehogs, from hunchbacks (1520s) to goblins (1580s) to bad girls (c.1530); meaning "poorly or raggedly clothed youngster" emerged 1550s, but was not in frequent use until after c.1780. Sea urchin is recorded from 1590s (a 19c. Newfoundland name for them was whore's eggs).
Urdu: official language of Pakistan, 1796, from Hindustani urdu "camp," from Turk. ordu (source of horde); short for zaban-i-urdu "language of the camp." Compare Dzongkha, a variant of Tibetan and the official language of Bhutan, literally "the language of the fortress."
ure (n.): "effect, operation, practice," early 15c., from Old French uevre (13c., Modern French oeuvre), from Latin opera (see opera).
urea: 1806, Latinized from French urée (1803), from Greek ouron "urine" (see urine).
uremia (n.): 1857, Modern Latin, from Greek ouron "urine" (see urine) + haima "blood" (see -emia).
ureter: 1570s, from medical Latin ureter, from Greek oureter, from ourein "to urinate," from ouron (see urine).
urethane: 1838, from French uréthane (Dumas, 1833), from urea + ethane.
urethra (n.): "canal through which urine is discharged from the bladder," 1630s, from Late Latin urethra, from Greek ourethra "the passage for urine," coined by Hippocrates from ourein "to urinate," from ouron (see urine).
urethritis (n.): 1823, from urethra + -itis.
urge (v.): 1550s, from Latin urgere "to press hard, push, drive, compel," from PIE root *werg- "to work" (cf. Avestan vareza "work, activity;" Greek ergon "work," orgia "religious performances," organon "tool;" Armenian gorc "work;" Lithuanian verziu "tie, fasten, squeeze," vargas "need, distress;" Old Church Slavonic vragu "enemy;" Gothic waurkjan, Old English wyrcan "work;" Gothic wrikan "persecute," Old English wrecan "drive, hunt, pursue;" Old Norse yrka "work, take effect"). Related: Urged; urging.
urge (n.): 1610s, from urge (v.); in frequent use after c.1910.
urgency (n.): 1530s; see urgent + -cy.
urgent (adj.): mid-15c., from Middle French urgent "pressing, impelling" (14c.), from Latin urgentem (nominative urgens), present participle of urgere "to press hard, urge" (see urge (v.)). Related: Urgently.
Uriah: masc. proper name, in Old Testament, the Hittite husband of Bathsheba; of non-Hebrew (possibly Horite) origin, but explained by folk etymology as Hebrew Uriyyah, literally "flame of the Lord." Uriah Heep, character from Dickens' "David Copperfield" (1850) sometimes is invoked as the type of a hypocritically humble person.
uric: 1797, from French urique, from urine (see urine). Uric acid attested from 1800.
urinal: late 13c., "glass vial to receive urine for medical inspection," from Old French urinal, from Late Latin urinal, from Latin urinalis (adj.) "relating to urine," from urina (see urine). Meaning "chamber pot" is from late 15c. Modern sense of "fixture for urinating (for men)" is attested from 1851.
urinalysis: 1889, from urine + analysis.
urinate (v.): 1590s, from Medieval Latin urinatus, past participle of urinare, from urina (see urine). Related: Urinated; urinating.
urine (n.): early 14c., from Old French urine (12c.), from Latin urina "urine," from PIE *ur- (cf. Greek ouron "urine"), variant of root *awer- "to moisten, flow" (cf. Sanskrit var "water," Avestan var "rain," Lithuanian jures "sea," Old English wær, Old Norse ver "sea," Old Norse ur "drizzling rain").
URL: by 1990, initialism from uniform resource locator.
urn (n.): late 14c., "vase used to preserve the ashes of the dead," from Latin urna "a jar, vessel," probably from earlier *urc-na, akin to urceus "pitcher, jug," and from the same source as Greek hyrke "earthen vessel." But another theory connects it to Latin urere "to burn" (cf. bust (n.1)).
uro-: word-forming element, from comb. form of Greek ouron "urine" (see urine).
urogenital (adj.): 1848, from uro- + genital. Form urinogenital is attested from 1836.
urologist (n.): 1889; see urology + -ist.
urology (n.): 1753, from uro- + -logy.
ursine (adj.): "pertaining to a bear," 1550s, from Latin ursinus "of or resembling a bear," from ursus "a bear," cognate with Greek arktos (see Arctic).
ursprache (n.): 1908, from German Ursprache, from ur- (see ur-) + sprache "speech" (see speech).
Ursula: fem. proper name, from Latin Ursula, diminutive of ursa "she-bear" (see ursine).
urticaria (n.): medical Latin, from Latin urtica "nettle," from urere "to burn." The native name is nettle-rash.
Uruguay: country named for river that flows past it, which is from a native name in an extinct language, said to represent uru "bird" + guay "tail," perhaps a reference to some totemic animal.
us (pron.): Old English us (cognate with Old Saxon, Old Frisian us, Old Norse, Swedish oss), accusative and dative plural of we, from PIE *ns- (cf. Sanskrit nas, Avestan na, Hittite nash "us;" Greek no "we two;" Latin nos "we, us;" Old Church Slavonic ny "us," nasu "our;" Old Irish ni, Welsh ni "we, us"). The -n- is preserved in Germanic in Dutch ons, German uns.
USA: also U.S.A., abbreviation of United States of America, in use by 1814 in addresses, etc.; not common otherwise before c.1920. Before then it often also meant United States Army.
usable (adj.): late 14c., from Old French usable (early 14c.), from user (see use). Not a common word before c.1840. Related: Usably.