Online Etymology Dictionary

-ward: adverbial suffix expressing direction, Old English -weard "toward," literally "turned toward," sometimes -weardes, with genitive singular ending of neuter adjectives, from Proto-Germanic *warth (cf. Old Saxon, Old Frisian -ward, Old Norse -verðr), variant of PIE *wert- "to turn, wind," from root *wer- (3) "to turn, bend" (see versus). The original notion is of "turned toward."
-worth: as final element in place names, from Old English worþ "enclosed place, homestead."
W: not in the Roman alphabet, but the Modern English sound it represents is close to the devocalized consonant expressed by Roman -U- or -V-. In Old English, this originally was written -uu-, but by 8c. began to be expressed by the runic character wyn (Kentish wen), which looked like this: ƿ (the character is a late addition to the online font set and doesn't display properly on many computers, so it's something like a cross between lower-case -p- and a reversed -y-). In 11c., Norman scribes introduced -w-, a ligatured doubling of Roman -u- which had been used on the continent for the Germanic "w" sound, and wyn disappeared c.1300. -W- is not properly a letter in the modern French alphabet, and it is used there only in borrowed foreign words, e.g. wagon, weekend, Western, whisky, wombat.
W.C. (n.): "lavatory," 1954, abbreviation of water closet.
WAC: 1943, American English, acronym from Women's Army Corps, formed 1943.
wack (n.): "crazy person," 1938, back-formation from from wacky. Adjective in slang sense of "worthless, stupid," is attested from late 1990s.
wacke (n.): rock resembling sandstone, 1803, from German Wacke, from Middle High German wacke "a large stone," from Old High German wacko "gravel," probably from Old High German wegan "to move." A miner's word, brought into geology by German geologist Abraham Gottlob Werner (1750-1817).
wacko (n.): extended form of wack, recorded from 1977.
wacky (adj.): "crazy, eccentric," 1935, variant of whacky (n.) "fool," late 1800s British slang, probably ultimately from whack "a blow, stroke," from the notion of being whacked on the head one too many times.
wad (n.): early 15c., "soft material for padding or stuffing," of uncertain origin, and the different meanings may represent more than one source. Among the possible connections are Medieval Latin wadda, Dutch watten, and Middle English wadmal (late 14c.) "woolen cloth," which seems to be from Old Norse vaðmal "a woolen fabric of Scandinavia," probably from vað "cloth" + mal "measure."

The meaning "bundle of currency" is American English, 1778. To shoot (one's) wad "do all one can do" is recorded from 1914. The immediate source of the expression probably is the sense of "disk of cloth used to hold powder and shot in place in a gun." Wad in slang sense of "a load of semen" is attested from 1920s, and the expression now often is felt in this sense. As a suffix, -wad in 1980s joined -bag, -ball, -head in combinations meaning "disgusting or unpleasant person."
wad (v.): 1570s, from wad (n.). Related: Wadded; wadding.
waddle (v.): "to walk with short steps," 1590s, frequentative of wade. Related: Waddled; waddling. The noun is recorded from 1690s.
wade (v.): Old English wadan "to go forward, proceed," in poetic use only, except as oferwaden "wade across," from Proto-Germanic *wadan (cf. Old Norse vaða, Danish vade, Old Frisian wada, Dutch waden, Old High German watan, German waten "to wade"), from PIE root *wadh- "to go," found only in Germanic and Latin (cf. Latin vadere "to go," vadum "shoal, ford," vadare "to wade"). Italian guado, French gué "ford" are Germanic loan-words.

Specifically of walking into water from c.1200. Originally a strong verb (past tense wod, past participle wad); weak since 16c. Figurative sense of "to go into" (action, battle, etc.) is recorded from late 14c. Related: Waded; wading.
waders (n.): "waterproof high boots," 1841, plural agent noun from wade.
wadi (n.): "watercourse," 1839, from Arabic wadi "seasonal watercourse," prop. participle of wada "it flowed."
wafer (n.): late 14c., from Anglo-French wafre, Old North French waufre "honeycomb, wafer," perhaps from Frankish (cf. Flemish wafer, altered from Middle Dutch wafel "honeycomb;" see waffle (n.)). Also found in Old French as gaufre, gofre "wafer, waffle." Eucharistic bread first so called 1550s.
waffle (n.): 1744, from Dutch wafel "waffle," from Middle Dutch or Middle Low German wafel, from Proto-Germanic *wabila- "web, honeycomb" (cf. Old High German waba "honeycomb," German Wabe), related to Old High German weban, Old English wefan "to weave" (see weave (v.)). Sense of "honeycomb" is preserved in some combinations referring to a weave of cloth. Waffle iron is from 1794.
waffle (v.): 1690s, "to yelp, bark," frequentative of waff "to yelp" (1610); possibly of imitative origin. Figurative sense of "talk foolishly" (1701) led to that of "vacillate, equivocate" (1803), originally a Scottish and northern English usage. Related: Waffled; waffling.
waft (v.): 1510s, "to carry over water," back-formation from obsolete wafter "convoy ship" (late 15c.), from Middle Dutch or Middle Low German wachter "a guard," from wachten "to guard," related to waken "rouse from sleep" (see wake (1)). The meaning "pass through air or space, float" is first attested 1704, and possibly shows some influence of northern dialect waff "cause to move to and fro" (1510s), a variant of wave. Related: Wafted; wafting.
wag (v.): early 13c., "waver, vacillate, lack steadfastness," probably from a Scandinavian source (cf. Old Norse vagga "a cradle," Danish vugge "rock a cradle," Old Swedish wagga "fluctuate"), and in part from Old English wagian "move backwards and forwards;" all from Proto-Germanic *wagojanan (cf. Old High German weggen, Gothic wagjan "to wag"), probably from PIE root *wegh- "to move about" (see weigh). Meaning "to move back and forth or up and down" is from c.1300. Wagtail is attested from c.1500 as a kind of small bird (late 12c. as a surname); 18c. as "a harlot," but seems to be implied much earlier:
If therefore thou make not thy mistress a goldfinch, thou mayst chance to find her a wagtaile. [Lyly, "Midas," 1592]
Wag-at-the-wall (1825) was an old name for a hanging clock with pendulum and weights exposed.
wag (n.): "person fond of making jokes," 1550s, perhaps a shortening of waghalter "gallows bird," person destined to swing in a noose or halter, applied humorously to mischievous children, from wag (v.) + halter. Or possibly directly from wag (v.).
wage (n.): c.1300, "a payment for services rendered," also in Middle English "a pledge of security" (mid-14c.), from Old North French wage (Old French guage) "pledge," from Frankish *wadja- (cf. Old English wedd, Gothic wadi "pledge"); see wed. Modern French cognate gages (plural) means "wages of a domestic," one of a plethora of French words for different classes, e.g. traitement (university professor), paye, salaire (workman), solde (soldier), récompense, prix. The Old English word was lean, related to loan and representing the usual Germanic form (cf. Gothic laun, Dutch loon, German lohn).
wage (v.): early 14c., "to pledge, deposit as a pledge," from Old North French wagier (Old French gagier), from wage (see wage (n.)). Meaning "to carry on" (of war, etc.) is attested from mid-15c., probably from earlier sense of "to offer as a gage of battle" (early 15c.). Related: Waged; waging.
wager (n.): c.1300, from Anglo-French wageure, from Old North French wagier "to pledge" (see wage (n.)).
wager (v.): c.1600, from wager (n.). Related: Wagered; wagering.
waggish (adj.): "willing to make a fool of oneself, and fond of doing so to others," 1580s, from wag (n.) + -ish. Related: Waggishly; waggishness.
waggle (v.): mid-15c., frequentative of wag (v.). Cf. Dutch waggelen "to waggle," Old High German wagon "to move, shake," German wackeln "to totter." Related: Waggled; waggling.
wagon (n.): 1520s, from Middle Dutch wagen, waghen, from Proto-Germanic *wagnaz (cf. Old English wægn, Modern English wain, Old Saxon and Old High German wagan, Old Norse vagn, Old Frisian wein, German Wagen), from PIE *woghnos, from *wegh- "to carry, to move" (cf. Sanskrit vahanam "vessel, ship," Greek okhos, Latin vehiculum, Old Church Slavonic vozu "carriage, chariot," Russian povozka, Lithuanian vazis "a small sledge," Old Irish fen, Welsh gwain "carriage, cart;" see weigh).

In Dutch and German, the general word for "a wheel vehicle;" English use is a result of contact through Flemish immigration, Dutch trade, or the Continental wars. It has largely displaced the native cognate, wain. Spelling preference varied randomly between -g- and -gg- from mid-18c., before American English settled on the etymological wagon, while waggon remained common in Great Britain. Wagon train is attested from 1810. Phrase on the wagon "abstaining from alcohol" is 1904, originally on the water cart.
wah-wah: 1926, in jazz slang, in reference to the effect on brass instruments made by manipulating the mute; of imitative origin. Later also in reference to an electric guitar effect. As an imitation of the sound of a baby crying, it is recorded from 1938. Wah-wah pedal is recorded from 1969. Cf. Chinook jargon wawa "talk, speak, call, ask, sermon, language;" Cree (Algonquian) wehwew "goose," Lenape (Algonquian) wava "snow goose," all probably of imitative origin.
Wahabi (n.): 1807, follower of Islamic fundamentalist Abd-el-Wahhab (1691-1787), from his name, with Arabic genitive suffix -i.
wahoo (n.): type of large marine fish, 1905, of unknown origin.
waif (n.): late 14c., "unclaimed property, flotsam, stray animal," from Anglo-Norm. waif, gwaif (early 13c.) "ownerless property," probably from a Scandinavian source akin to Old Norse veif "waving thing, flag," from Proto-Germanic *waif-, from PIE *weip- "to turn, vacillate, tremble ecstatically" (see vibrate). Cf. Medieval Latin waivium "thing thrown away by a thief in flight." A Scottish/northern English parallel form was wavenger (late 15c.).

Meaning "person (especially a child) without home or friends" first attested 1784, from legal phrase waif and stray (1620s). Neglected children being uncommonly thin, the word tended toward this sense. Connotations of "fashionable, small, slender woman" began 1991 with application to childishly slim supermodels, e.g. Kate Moss.
waifish (adj.): 1870, from waif + -ish. Related: Waifishly; waifishness.
wail (v.): early 14c., from Old Norse væla "to lament," from væ "woe" (see woe). Of jazz musicians, "to play very well," attested from 1955, American English slang (wailing "excellent" is attested from 1954). Related: Wailed.
wail (n.): c.1400; see wail (v.).
wain (n.): Old English wægn "wheeled vehicle," from Proto-Germanic *wagnaz (see wagon). Largely fallen from use by c.1600, but kept alive by poets, who found it easier to rhyme on than wagon. As a name for the Big Dipper/Plough, it is from Old English (see Charles's Wain).
wainscot (n.): mid-14c., "imported oak of superior quality," probably from Middle Dutch or Middle Flemish waghenscote "superior quality oak wood, board used for paneling" (though neither of these is attested as early as the English word), related to Middle Low German wagenschot (late 14c.), from waghen (see wagon) + scote "partition, crossbar." So called perhaps because the wood originally was used for wagon building and coachwork. Meaning "panels lining the walls of rooms" is recorded from 1540s. Wainscoting is from 1570s.
wainwright (n.): "wagon-builder," Old English wægn-wyrhta; see wain + wright.
waist (n.): "middle part of the body," also "part of a garment fitted for the waist," late 14c., probably from Old English *wæst "growth," hence, "where the body grows," from Proto-Germanic *wahs-tu- (cf. Old English wæstm, Old Norse vaxtr, Swedish växt, Old High German wahst "growth, increase," Gothic wahstus "stature," Old English weaxan "to grow" see wax (v.)), from PIE *wegs-, extended form of root *aug- "to increase" (see augment). Meaning "portion of a garment that covers the waist" (but, due to fashion styles, often is above or below it) is from 1640s.
waistcoat (n.): 1510s, from waist + coat (n.).
waisted (adj.): c.1400, "fitted with a (specified type of) waist," from waist.
waistline (n.): also waist-line, 1867, from waist + line (n.).
wait (v.): c.1200, "to watch with hostile intent, lie in wait for," from Old North French waitier "to watch" (Old French gaitier, Modern French guetter), from Frankish *wahton (cf. Dutch wacht "a watching," Old High German wahten, German wachten "to watch, to guard;" Old High German wahhon "to watch, be awake," Old English wacian "to be awake;" see wake (v.)). General sense of "remain in some place" is from late 14c.; that of "to see to it that something occurs" is late 14c. Meaning "to stand by in attendance on" is late 14c.; specific sense of "serve as an attendant at a table" is from 1560s. Related: Waited; waiting.

To wait (something) out "endure a period of waiting" is recorded from 1909, originally American English, in reference to baseball batters trying to draw a base on balls. Waiting game is recorded from 1890. Waiting room is attested from 1680s. Waiting list is recorded from 1897; the verb wait-list "to put (someone) on a waiting list" is recorded from 1960.
wait (n.): early 13c., "a watcher, onlooker," from Old North French wait, Old French gaite, from gaitier (see wait (v.)). From late 14c. as "an ambush, a trap" (as in lie in wait).
waiter (n.): late 14c., "attendant, watchman," agent noun from wait (v.). Sense of "servant who waits at tables" is from late 15c., originally in reference to household servants; in reference to inns, eating houses, etc., it is attested from 1660s.
waitress (n.): 1834; see waiter + -ess.
waitstaff (n.): 1981, American English; see waiter + staff (n.).
waive (v.): c.1300, from Anglo-French weyver "to abandon, waive," Old French weyver, guever "to abandon, give back," probably from a Scandinavian source akin to Old Norse veifa "to swing about," from Proto-Germanic *waibijanan (see waif). In Middle English legal language, used of rights, goods, or women. Related: Waived; waiving.
waiver (n.): "act of waiving," 1620s (modern usage is often short for waiver clause); from Anglo-French legal usage of infinitive as a noun (see waive). Baseball waivers is recorded from 1907. Other survivals of noun use of infinitives in Anglo-French legalese include disclaimer, merger, rejoinder, misnomer, ouster, retainer, attainder.
wake (v.): "to become awake," Old English wacan "to become awake," also from wacian "to be or remain awake," both from Proto-Germanic *waken (cf. Old Saxon wakon, Old Norse vaka, Danish vaage, Old Frisian waka, Dutch waken, Old High German wahhen, German wachen "to be awake," Gothic wakan "to watch"), from PIE root *weg- "to be strong, be lively" (cf. Sanskrit vajah "force, swiftness, race, prize," vajayati "drives on;" Latin vegere, vigere "to be live, be active, quicken," vigil "awake, wakeful," vigor "liveliness, activity"). Causative sense "to rouse from sleep" is attested from c.1300. Related: Waked; waking. Phrase wake-up call is attested from 1976, originally a call one received from the hotel desk in the morning.