Online Etymology Dictionary

Valentino (n.): "gigolo, good-looking romantic man," 1927, from Italian-born U.S. movie actor Rudolph Valentino (1895-1926), who was adored by female fans. His full name was Rodolfo Guglielmi di Valentino, from the Latin masc. proper name Valentinus (see Valentine).
valerian (n.): plant of Eurasia, cultivated for its medicinal root, late 14c., from Old French valeriane "wild valerian" (13c.), apparently from feminine singular of Latin adjective Valerianus, from the personal name Valerius (see Valerie); but Weekley writes, "some of the German and Scand. forms of the name point rather to connection with the saga-hero Wieland."
Valerie: fem. proper name, French, from Latin Valeria, fem. of Valerius, name of a Roman gens, from valere "to be strong" (see valiant).
valet (n.): "personal man-servant," mid-14c. (late 12c. as a surname), from Old French valet, variant of vaslet "man's servant, workman's assistant," originally "squire, young man, youth of noble birth" (12c.), from Gallo-Roman *vassellittus "young nobleman, squire, page," diminutive of Medieval Latin vassallus, from vassus "servant" (see vassal). Modern sense is usually short for valet de chambre; the general sense of "male household servant of the meaner sort" going with the variant form varlet. First recorded use of valet parking is from 1959.
valetudinarian (n.): "one who is constantly concerned with his own ailments," 1703, from valetudinary (1580s), from Latin valetudinarius, from valetudo "state of health" (either good or bad), from valere "be strong" (see valiant) + -tudo, abstract noun suffix (see -tude). Valetudinary (adj.) "sickly" is recorded from 1580s.
valgus (adj.): deformity in which a bone or joint is twisted outward from the center of the body; form of club-foot, 1800, from Latin valgus "bandy-legged, bow-legged, having the legs bent outward." Said to be probably related to Sanskrit valgati "to move up and down," Old English wealcan "to roll, move to and fro" (see walk (v.)), perhaps on the notion of "go irregularly or to and fro" [Tucker]. "Yet the main characteristic of 'bow-legged' is the crookedness of the legs, not 'going up and down' or 'to and fro'" [de Vaan] and there are phonetic difficulties. A classical word used in a different sense in modern medicine; also see varus.
Valhalla (n.): heavenly hall in which Odin receives the souls of heroes slain in battle, 1696 (in Archdeacon Nicolson's "English Historical Library"), from Old Norse Valhöll "hall of the battle-slain;" first element from valr "those slain in battle," from Proto-Germanic *walaz (source also of Old English wæl "slaughter, bodies of the slain," Old High German wal "battlefield, slaughter"), from PIE root *wele- (2) "to strike, wound" (source also of Avestan vareta- "seized, prisoner," Latin veles "ghosts of the dead," Old Irish fuil "blood," Welsh gwel "wound"). Second element is from höll "hall," from PIE root *kel- (2) "to conceal" (see cell). Reintroduced by 18c. antiquaries. Figurative sense is from 1845.
valiance (n.): "valiant character" (obsolete or archaic), mid-15c., earlier vailance (late 14c.), from Anglo-French vaillaunce, valiauns (c. 1300) or Old French vaillance "value, price; merit, worth; virtue, fine qualities; courage, valor" (12c.), from Old French valiant (see valiant).
valiant (adj.): early 14c. (late 12c. in surnames), "brave, courageous, intrepid in danger," from Anglo-French vaylant, and Old French vaillant "stalwart, brave," present participle adjective from valoir "be worthy," originally "be strong," from Latin valere "be strong, be well, be worth, have power, be able, be in health," from PIE root *wal- "be strong" (source also of Old English wealdan "to rule," Old High German -walt, -wald "power" (in personal names), Old Norse valdr "ruler," Old Church Slavonic vlasti "to rule over," Lithuanian valdyti "to have power," Celtic *walos- "ruler," Old Irish flaith "dominion," Welsh gallu "to be able"). As a noun, "valiant person," from c. 1600. Related: Valiantly.
valid (adj.): 1570s, "having force in law, legally binding," from Middle French valide (16c.), from Latin validus "strong, effective, powerful, active," from valere "be strong" (see valiant). The meaning "sufficiently supported by facts or authority, well-grounded" is first recorded 1640s.
validate (v.): 1640s, from Medieval Latin validatus, past participle of validare "to make valid," from validus (see valid). Related: Validated; validating.
validation (n.): "act of giving validity," 1650s, noun of action from validate.
validity (n.): 1540s, from Middle French validité or directly from Late Latin validitatem (nominative validitas) "strength," from Latin validus (see valid).
valise (n.): 1610s, "suitcase, soldier's kit bag," from Middle French valise (16c.), from Italian valigia, of uncertain origin. Attested in Medieval Latin forms valisia (early 15c.), valixia (late 13c.). "The name is generally given to a leather case of moderate size, opening wide on a hinge or like a portfolio ...." [Century Dictionary]
Valium (n.): 1961, proprietary name (Hoffmann-La Roche Inc., Nutley, N.J.) of diazepam (reg. U.S.), of unknown origin.
Valkyr (n.): see Valkyrie.
Valkyrie (n.): 1768, one of 12 war-maidens who escorted the brave dead to Valhalla, from Old Norse valkyrja, literally "chooser of the slain," from valr "those slain in battle" (see Valhalla) + kyrja "chooser," from ablaut root of kjosa "to choose," from Proto-Germanic *keusan, from PIE *geus- "to taste, choose" (see gusto). Old English form was Wælcyrie, but they seem not to have figured as largely in Anglo-Saxon tales as in Scandinavian. German Walküre (Wagner) is from Norse. Related: Valkyrian.
valley (n.): c. 1300, from Anglo-French valey, Old French valee "a valley" (12c.), from Vulgar Latin *vallata, from Latin vallis "valley," of unknown origin. Valley Girl (in reference to San Fernando Valley of California) was popularized 1982 in song by Frank Zappa and his daughter. Valley of Death (Psalm xxiii:4) was rendered in Middle English as Helldale (mid-13c.).
valor (n.): c. 1300, "value, worth," from Old French valor, valour "valor, moral worth, merit, courage, virtue" (12c.), from Late Latin valorem (nominative valor) "value, worth" (in Medieval Latin "strength, valor"), from stem of Latin valere "be strong, be worth" (see valiant). The meaning "courage" is first recorded 1580s, from Italian valore, from the same Late Latin word. (The Middle English word also had a sense of "worth or worthiness in respect of manly qualities").
valorization (n.): 1906, from valor "value" (late 15c.), variant of valour (see valor).
valorize (v.): 1908, from valor (see valorization) + -ize.
valorous (adj.): late 15c., from Middle French valeureux, from valeur (see valor). Related: Valorously; valorousness.
valour (n.): chiefly British English spelling of valor (q.v.); for spelling, see -or.
valuable (adj.): "of great value or price," 1580s, from value (v.) + -able. As a noun, "a valuable thing," from 1775 (in modern use often in plural). Related: Valuably.
valuables (n.): see valuable.
valuation (n.): 1520s, from Middle French valuation, noun of action from valuer, from Old French valoir (see value (n.)).
value (n.): c. 1300, "price equal to the intrinsic worth of a thing;" late 14c., "degree to which something is useful or estimable," from Old French value "worth, price, moral worth; standing, reputation" (13c.), noun use of fem. past participle of valoir "be worth," from Latin valere "be strong, be well; be of value, be worth" (see valiant). The meaning "social principle" is attested from 1918, supposedly borrowed from the language of painting. Value judgment (1889) is a loan-translation of German Werturteil.
value (v.): mid-15c., "estimate the value of," also "think highly of," probably from value (n.). Related: Valued, valuing.
valueless (adj.): 1590s, from value (n.) + -less. Related: Valuelessness.
values (n.): "principles, standards," 1918, from plural of value (n.).
valve (n.): late 14c., "one of the halves of a folding door," from Latin valva (plural valvae) "section of a folding or revolving door," literally "that which turns," related to volvere "to roll" (see volvox). Sense extended 1610s to "membranous fold regulating flow of bodily fluids;" 1650s to "mechanical device that works like an anatomical valve;" and 1660s in zoology to "halves of a hinged shell." Related: Valved.
vambrace (n.): armor or guard for the forearm, early 14c., from Anglo-French vant-bras, from Old French avant-bras, from avant "before, in front of" (see avant) + bras "an arm" (see brace (n.)).
vamoose (v.): "to decamp, be off," 1834, from Spanish vamos "let us go," from Latin vadamus, first person plural indicative of vadere "to go, to walk, go hastily," from PIE root *wadh- (2) "to go" (source also of Old English wadan "to go," Latin vadum "ford;" see wade (v.)).
vamp (v.): "extemporize on a piano," 1789, from vamp (n.1) "upper part of a shoe or boot," via verbal sense of "provide a stocking (later a shoe) with a new vamp" (1590s), then "patch up, repair" (compare revamp). Related: Vamped; vamping.
vamp (n.2): "seductive woman who exploits men," 1911, short for vampire. First attested use is earlier than the release of the Fox film "A Fool There Was" (January 1915), with sultry Theda Bara in the role of The Vampire. The movie was based on a play of that name that had been on Broadway in 1909 (title and concept from a Kipling poem, "The Vampire," inspired by a Burne-Jones painting). The stage lead seems to have been played by Kathryn Kaelred and Bernice Golden Henderson. At any rate, Bara (born Theodosia Goodman) remains the classic vamp and the word's wide currency is attributable to her performance.
A fool there was and he made his prayer
(Even as you and I!)
To a rag and a bone and a hank of hair
(We called her the woman who did not care)
But the fool, he called her his lady fair
(Even as you and I.)

[Kipling, "The Vampire"]
vamp (n.1): "upper of a shoe or boot," 1650s, earlier "part of a stocking that covers the foot and ankle" (c. 1200), from Anglo-French *vaumpé, from Old French avantpié "vamp of a shoe," from avant "in front" (see avant) + pié "foot," from Latin pes, from PIE root *ped- (1) "a foot" (see foot (n.)).
vampire (n.): spectral being in a human body who maintains semblance of life by leaving the grave at night to suck the warm blood of the living as they sleep, 1734, from French vampire (18c.) or German Vampir (1732, in an account of Hungarian vampires), from Hungarian vampir, from Old Church Slavonic opiri (source also of Serbian vampir, Bulgarian vapir, Ukrainian uper), said by Slavic linguist Franc Miklošič to be ultimtely from Kazan Tatar ubyr "witch," but Max Vasmer, an expert in this linguistic area, finds that phonetically doubtful. An Eastern European creature popularized in English by late 19c. gothic novels, however there are scattered English accounts of night-walking, blood-gorged, plague-spreading undead corpses from as far back as 1196. Figurative sense of "person who preys on others" is from 1741. Applied 1774 by French biologist Buffon to a species of South American blood-sucking bat. Related: Vampiric.
vampirism (n.): 1737, from vampire + -ism.
van (n.1): "front part of an army or other advancing group," c. 1600, shortening of vanguard.
van (n.2): "covered truck or wagon," 1829, shortening of caravan. Century Dictionary suggests this was perhaps regarded as *carry-van.
Van Allen: name of radiation belts around the Earth (and certain other planets), 1959, from U.S. physicist James A. Van Allen (1914-2006), who reported them in 1958.
van de Graaff: in reference to an electrostatic charge generator, 1934, named for U.S. physicist R.J. van de Graaff (1901-1967).
vanadium (n.): rare metallic element, 1833, named 1830 by Swedish chemist Nils Gabriel Sefström (1787-1845), from Old Norse Vanadis, one of the names of the Norse beauty goddess Freyja (perhaps from PIE *wen- (1) "to desire, strive for," which would connect it to Venus); the metal perhaps so called for of its colorful compounds (an earlier name for it was erythronium, for the redness of its salts when heated). With metallic element ending -ium. Related: Vanadous; vanadious.
Vancouver: Canadian city, settled 1865, named for the island, which was named for English navigator George Vancouver (1757-1798) who sailed with Capt. Cook and surveyed the Pacific coast in this area in 1792.
vandal (n.): 1660s, "willful destroyer of what is beautiful or venerable," from Vandals, name of the Germanic tribe that sacked Rome in 455 under Genseric, from Latin Vandalus (plural Vandali), from the tribe's name for itself (Old English Wendlas), perhaps from Proto-Germanic *wandljaz "wanderer." The literal historical sense in English is recorded from 1550s.
There does not seem to be in the story of the capture of Rome by the Vandals any justification for the charge of willful and objectless destruction of public buildings which is implied in the word 'vandalism.' It is probable that this charge grew out of the fierce persecution which was carried on by [the Vandal king] Gaiseric and his son against the Catholic Christians, and which is the darkest stain on their characters. ["Encyclopaedia Britannica," 13th ed., 1926]
vandalism (n.): 1794, from French vandalisme, first used by Henri Grégoire, Bishop of Blois, in a report decrying the pillage and destruction of art in the course of the French Revolution; see vandal + -ism.
vandalize (v.): by 1797, from vandal + -ize. Related: Vandalized; vandalizing. A past participle vandald is recorded from 1640s..
vandyke (n.): "short, pointed beard," 1894, from the style shown on portraits by Flemish painter Anton Van Dyck (1599-1641); earlier "a type of collar with a deep cut edge" (1755) also from a style depicted in his paintings.
vane (n.): "plate metal wind indicator," early 15c., southern England alteration (see V) of fane "flag, banner."
Vanessa: fem. proper name, also the name of a butterfly genus. As a name, not much used in U.S. before 1950. It appears to have been coined by Swift c. 1711 as a pseudonym for Esther Vanhomrigh, who was romantically attached to him, and composed of elements of her name. He used it in private correspondence and published it in the poem "Cadenus and Vanessa" (1713).
The name Cadenus is an anagram of Decanus; that of Vanessa is formed much in the same way, by placing the first syllable of her sir-name before her christian-name, Hessy. [William Monck Mason, "History and Antiquities of the Collegiate and Cathedral Church of St. Patrick, Near Dublin," 1820]
As the name of a genus of butterflies that includes the Red Admiral and the Painted Lady, it dates to 1808, chosen by Danish entomologist Johan Christian Fabricius (1745-1808) for unknown reasons. He has no obvious connection to Swift, and the theory that it was intended for *Phanessa, from Greek phanes "a mystical divinity in the Orphic system" does no honor to his classical learning.