Online Etymology Dictionary

watery (adj.): Old English wæterig; see water (n.1) + -y (2). Related: Wateriness.
watt (n.): unit of electrical power, 1882, in honor of James Watt (1736-1819), Scottish engineer and inventor. The surname is from an old pet form of Walter and also is in Watson.
wattage (n.): 1897, from watt + -age.
wattle (n.2): "fleshy appendage below the neck of certain birds," 1510s (extended jocularly to human beings, 1560s), of uncertain origin and of doubtful relationship to wattle (n.1). Related: Wattled.
wattle (n.1): "stakes interlaced with twigs and forming the framework of the wall of a building," Old English watol "hurdle," in plural "twigs, thatching, tiles," related to weðel "bandage," from Proto-Germanic *wadlaz, from PIE *au- (3) "to weave" (see weeds). Surviving in wattle-and-daub "building material for huts, etc." (1808).
Watusi (n.): racial group in Rwanda and Burundi (also called Tutsi), 1899. As the name of a popular dance, attested from 1964.
wave (v.): "move back and forth," Old English wafian "to wave, fluctuate" (related to wæfre "wavering, restless, unstable"), from Proto-Germanic *wab- (source also of Old Norse vafra "to hover about," Middle High German waben "to wave, undulate"), possibly from PIE root *webh- "to move to and fro; to weave" (see weave (v.)). Transitive sense is from mid-15c.; meaning "to make a sign by a wave of the hand" is from 1510s. Related: Waved; waving.
I was much further out than you thought
And not waving but drowning.
[Stevie Smith]
wave (n.): "moving billow of water," 1520s, alteration (by influence of wave (v.)) of Middle English waw, which is from Old English wagian "to move to and fro" (cognate with Old Saxon, Old High German wag, Old Frisian weg, Old Norse vagr "water in motion, wave, billow," Gothic wegs "tempest;" see wag (v.)). The usual Old English word for "moving billow of water" was yð.

The "hand motion" meaning is recorded from 1680s; meaning "undulating line" is recorded from 1660s. Of people in masses, first recorded 1852; in physics, from 1832. Sense in heat wave is from 1843. The crowd stunt in stadiums is attested under this name from 1984, the thing itself said to have been done first Oct. 15, 1981, at the Yankees-A's AL championship series game in the Oakland Coliseum; soon picked up and popularized at University of Washington. To make waves "cause trouble" is attested from 1962.
wavelength (n.): also wave-length, 1850, "distance between peaks of a wave," from wave (n.) + length. Originally of spectra; radio sense is attested by 1925. Figurative sense of "mental harmony" is recorded from 1927, on analogy of radio waves.
waveless (adj.): 1590s, from wave (n.) + -less.
wavelet (n.): 1808, mainly in poetry, from wave (n.) + diminutive suffix -let.
waver (v.): late 13c., weyveren, "to show indecision," probably related to Old English wæfre "restless, wavering," from Proto-Germanic *wæbraz (source also of Middle High German wabern "to waver," Old Norse vafra "to hover about"), a frequentative form from the root of wave (v.). Related: Wavered; wavering.
wavy (adj.): 1580s, from wave (n.) + -y (2). Related: Waviness.
wax (n.): Old English weax "substance made by bees," from Proto-Germanic *wahsam (source also of Old Saxon, Old High German wahs, Old Norse vax, Dutch was, German Wachs), from PIE root *wokso- "wax" (source also of Old Church Slavonic voskŭ, Lithuanian vaškas, Polish wosk, Russian vosk "wax" (but these may be from Germanic). Used of other similar substances from 18c. Slang for "gramophone record" is from 1932, American English (until the early 1940s, most original records were made by needle-etching onto a waxy disk which was then metal-plated to make a master). Waxworks "exhibition of wax figures representing famous or notorious persons" first recorded 1796.
wax (v.): "grow bigger or greater," Old English weaxan "to increase, grow" (class VII strong verb; past tense weox, past participle weaxen), from Proto-Germanic *wahsan (source also of Old Saxon, Old High German wahsan, Old Norse vaxa, Old Frisian waxa, Dutch wassen, German wachsen, Gothic wahsjan "to grow, increase"), from PIE *weg- (source also of Sanskrit vaksayati "cause to grow," Greek auxein "to increase"), extended form of root *aug- (1) "to increase" (see augment). Strong conjugation archaic after 14c. Related: Waxed; waxing.
wax-paper (n.): 1812, from wax (n.) + paper (n.).
waxen (adj.): Old English wexen; see wax (n.) + -en (2).
waxwing (n.): 1817, from wax (n.) + wing (n.). So called for appendages at the tips of its feathers which look like red sealing-wax.
waxy (adj.): early 15c., "made of wax," from wax (n.) + -y (2). Figurative use from 1590s. Meaning "like wax" is from 1799. Related: Waxiness.
way (n.): Old English weg "road, path; course of travel; room, space, freedom of movement;" also, figuratively, "course of life" especially, in plural, "habits of life" as regards moral, ethical, or spiritual choices, from Proto-Germanic *wegaz (source also of Old Saxon, Dutch weg, Old Norse vegr, Old Frisian wei, Old High German weg, German Weg, Gothic wigs "way"), from PIE *wegh- "to move" (see weigh).

From c. 1300 as "manner in which something occurs." Adverbial constructions attested since Middle English include this way "in this direction," that way "in that direction," both from late 15c.; out of the way "remote" (c. 1300). In the way "so placed as to impede" is from 1560s.

From the "course of life" sense comes way of life (c. 1600), get (or have) one's way (1590s), have it (one's) way (1709). From the "course of travel" sense comes the figurative go separate ways (1837); one way or (the) other (1550s); have it both ways (1847); and the figurative sense of come a long way (1922).

Adverbial phrase all the way "completely, to conclusion" is by 1915; sexual sense implied by 1924. Make way is from c. 1200. Ways and means "resources at a person's disposal" is attested from early 15c. Way out "means of exit" is from 1926. Encouragement phrase way to go is short for that's the way to go.
way (adv.): c. 1200, short for away (adv.). Many expressions involving this are modern and American English colloquial, such as way-out "far off;" way back "a long time ago" (1887); way off "quite wrong" (1892). Any or all of these might have led to the slang adverbial meaning "very, extremely," attested by 1984 (as in way cool).
way-out (adj.): 1868, "far off," from way (adv.), short for away, + out. Sense of "original, bold," is jazz slang from 1940s, probably suggesting "far off" from what is conventional or expected.
wayfarer (n.): mid-15c., agent noun from way (n.) + fare (v.). Earlier was wayferer (late 14c.). The brand of sunglasses (manufactured by Ray-Ban) dates to 1952.
wayfaring (n.): 14c., modification of Old English wegfarende "wayfaring;" see way (n.) + fare (v.).
waylay (v.): "to ambush," 1510s, from way (n.) + lay (v.), on model of Middle Low German, Middle Dutch wegelagen "besetting of ways, lying in wait with evil or hostile intent along public ways." Related: Waylaid; waylaying.
Wayne: surname, by 1319, variant of Wain, representing wainwright, wainer (see wain) or perhaps "one who dwells by the tavern with the sign of the wain."
wayside (n.): "the side of the road," c. 1400, from way (n.) + side (n.). To fall by the wayside is from Luke viii:5.
wayward (adj.): late 14c., shortening of aweiward "turned away," from way (adv.), shortening of away + -ward. Related: Waywardly; waywardness.
we (pron.): Old English we, first person plural pronoun, "I and another or others," from Proto-Germanic *wiz (source also of Old Saxon wi, Old Norse ver, Danish vi, Old Frisian wi, Dutch wij, Old High German and German wir, Gothic weis "we"), from PIE *we- (source also of Sanskrit vayam, Old Persian vayam, Hittite wesh "we," Old Church Slavonic ve "we two," Lithuanian vedu "we two").

The "royal we" (use of plural pronoun to denote oneself) is at least as old as "Beowulf" (c.725); use by writers to establish an impersonal style is also from Old English; it was especially common 19c. in unsigned editorials, to suggest staff consensus, and was lampooned as such since at least 1853 (see wegotism).
weak (adj.): c. 1300, from Old Norse veikr "weak," cognate with Old English wac "weak, pliant, soft," from Proto-Germanic *waikwa- "yield" (source also of Old Saxon wek, Swedish vek, Middle Dutch weec, Dutch week "weak, soft, tender," Old High German weih "yielding, soft," German weich "soft"), from PIE root *weik- (4) "to bend, wind" (see vicarious).

Sense of "lacking authority" is first recorded early 15c.; that of "lacking moral strength" late 14c. In grammar, denoting a verb inflected by regular syllabic addition rather than by change of the radical vowel, from 1833. Related: Weakly. Weak-kneed "wanting in resolve" is from 1870.
weaken (v.): late 14c., "to become feeble," from weak + -en (1). Transitive sense from 1560s. Related: Weakened; weakening.
weakfish (n.): 1838, from Dutch weekvisch, from week "soft" (see weak). So called because it does not pull hard when hooked.
weakling (n.): 1520s, coined by Tyndale from weak (adj.) + -ling as a loan-translation of Luther's Weichling "effeminate man" (from German weich "soft") in I Cor. vi.9, where the Greek is malakoi, from malakos "soft, soft to the touch," "Like the Lat. mollis, metaph. and in a bad sense: effeminate, of a catamite, a male who submits his body to unnatural lewdness" ["Thayer's Greek-English Lexicon of the New Testament"].
weakness (n.): c. 1300, "quality of being weak," from weak + -ness. Meaning "a disadvantage, vulnerability" is from 1590s. That of "self-indulgent fondness" is from 1712; meaning "thing for which one has an indulgent fondness" is from 1822.
weal (n.1): "well-being," Old English wela "wealth," in late Old English also "welfare, well-being," from West Germanic *welon-, from PIE root *wel- (2) "to wish, will" (see will (v.)). Related to well (adv.).
weal (n.2): "raised mark on skin," 1821, alteration of wale (q.v.).
weald (n.): Old English (West Saxon) weald "forest, woodland," specifically the forest between the North and South Downs in Sussex, Kent, and Surrey; a West Saxon variant of Anglian wald (see wold). Related: Wealden.
wealth (n.): mid-13c., "happiness," also "prosperity in abundance of possessions or riches," from Middle English wele "well-being" (see weal (n.1)) on analogy of health.
wealthy (adj.): late 14c., "happy, prosperous," from wealth + -y (2). Meaning "rich, opulent" is from early 15c. Noun meaning "wealthy persons collectively" is from late 14c.
wean (v.): "train (an infant or animal) to forego suckling," c. 1200, from Old English wenian "to accustom, habituate," from Proto-Germanic *wanjan (source also of Old Norse venja, Dutch wennen, Old High German giwennan, German gewöhnen "to accustom"), from PIE *won-eyo-, causative form of root *wen- (1) "to desire, strive for" (see Venus).

The sense of "accustom a child to not suckling from the breast" in Old English generally was expressed by gewenian or awenian, which has a sense of "unaccustom" (compare German abgewöhnen, entwöhnen "to wean," literally "to unaccustom"). The modern word might be one of these with the prefix worn off, or it might be wenian in a specialized sense of "accustom to a new diet." Figurative extension to any pursuit or habit is from 1520s.
weanling (n.): 1530s, from wean + -ling.
weapon (n.): Old English wæpen "instrument of fighting and defense, sword," also "penis," from Proto-Germanic *wæpnan (source also of Old Saxon wapan, Old Norse vapn, Danish vaaben, Old Frisian wepin, Middle Dutch wapen, Old High German wafan, German Waffe "weapon"), from *webno-m, of unknown origin with no cognates outside Germanic.
weaponry (n.): 1812, from weapon + -ry.
weapons of mass destruction (n.): "nuclear, biological and chemical weapons" attested by 1946, apparently first used (in Russian) by the Soviets.
The terms "weapons of mass destruction" and "WMD" mean chemical, biological, and nuclear weapons, and chemical, biological, and nuclear materials used in the manufacture of such weapons. [United States Code: Title 50, "War and National Defense," chapter 43, § 2902, 2009]
wear (v.): Old English werian "to clothe, put on, cover up," from Proto-Germanic *wazjan (source also of Old Norse verja, Old High German werian, Gothic gawasjan "to clothe"), from PIE *wos-eyo-, from root *wes- (4) "to clothe" (source also of Sanskrit vaste "he puts on," vasanam "garment;" Avestan vah-; Greek esthes "clothing," hennymi "to clothe," eima "garment;" Latin vestire "to clothe;" Welsh gwisgo, Breton gwiska; Old English wæstling "sheet, blanket;" Hittite washshush "garments," washanzi "they dress").

The Germanic forms "were homonyms of the vb. for 'prevent, ward off, protect' (Goth. warjan, O.E. werian, etc.), and this was prob. a factor in their early displacement in most of the Gmc. languages" [Buck]. Shifted from a weak verb (past tense and past participle wered) to a strong one (past tense wore, past participle worn) in 14c. on analogy of rhyming strong verbs such as bear and tear. Secondary sense of "use up, gradually damage" (late 13c.) is from effect of continued use on clothes. To wear down (transitive) "overcome by steady force" is from 1843. To wear off "diminish by attrition or use" is from 1690s.
wear (n.): "action of wearing" (clothes), mid-15c., from wear (v.). Meaning "what one wears" is 1560s. To be the worse for wear is attested from 1782; noun phrase wear and tear is first recorded 1660s, implying the sense "process of being degraded by use."
wearisome (adj.): mid-15c., "weary," also "causing weariness," from weary + -some (1).
weary (adj.): Old English werig "tired, exhausted; miserable, sad," related to worian "to wander, totter," from Proto-Germanic *worigaz (source also of Old Saxon worig "weary," Old High German wuorag "intoxicated"), of unknown origin.
weary (v.): Old English wergian "to be or become tired" (intransitive), gewergian "to exhaust, to make tired" (transitive), from the source of weary (adj.). Related: Wearied; wearying.
weasel (n.): Old English weosule, wesle "weasel," from Proto-Germanic *wisulon (source also of Old Norse visla, Middle Dutch wesel, Dutch wezel, Old High German wisula, German Wiesel), probably related to Proto-Germanic *wisand- "bison" (see bison), with a base sense of "stinking animal," because both animals have a foul, musky smell (compare Latin vissio "stench"). A John Wesilheued ("John Weaselhead") turns up on the Lincolnshire Assize Rolls for 1384, but the name seems not to have endured, for some reason. Related: Weaselly.