Online Etymology Dictionary

aviator (n.): "aircraft pilot," 1887, from French aviateur, from Latin avis (see aviary) + -ateur. Also used c. 1891 in a sense of "aircraft." Feminine form aviatrix is from 1927; earlier aviatrice (1910), aviatress (1911).
Avicenna: Latinization of name of Ibn Sina (980-1037), Persian philosopher and physician. Full name Abū 'Alī al-Husayn ibn 'Abd Allāh ibn Sīnā al-Balkhī.
aviculture (n.): 1876, from French aviculture, from Latin avis "bird" (see aviary) + Latin cultura "cultivation" (see culture).
avid (adj.): 1769, from French avide (15c.), from Latin avidus "longing eagerly, desirous, greedy," from avere "to desire eagerly." Also in part a back-formation from avidity. Related: Avidly.
avidity (n.): mid-15c., "eagerness, zeal," from Old French avidite "avidity, greed," from Latin aviditatem (nominative aviditas) "eagerness, avidity," noun of quality from avidus (see avid).
avionics (n.): 1949, from aviation + electronics.
Avis: U.S. car rental company, according to company history, founded 1946 at Willow Run Airport in Detroit by Warren Avis.
avocado (n.): 1763, from Spanish avocado, altered (by folk etymology influence of earlier Spanish avocado "lawyer," from same Latin source as advocate (n.)) from earlier aguacate, from Nahuatl (Aztecan) ahuakatl "avocado" (with a secondary meaning "testicle" probably based on resemblance), from proto-Nahuan *pawa "avocado." As a color-name, first attested 1945. The English corruption alligator (pear) is 1763, from Mexican Spanish alvacata, alligato.
avocation (n.): 1520s, "a calling away from one's occupation," from Latin avocationem (nominative avocatio) "a calling away, distraction, diversion," noun of action from past participle stem of avocare, from ab- "off, away from" (see ab-) + vocare "to call" (see voice (n.)).
avoid (v.): c. 1300, from Anglo-French avoider "to clear out, withdraw (oneself)," partially Englished from Old French esvuidier "to empty out," from es- "out" (see ex-) + vuidier "to be empty," from voide "empty, vast, wide, hollow, waste" (see void (adj.)). Originally a law term; modern sense of "have nothing to do with" also was in Middle English and corresponds to Old French eviter with which it was perhaps confused. Meaning "escape, evade" first attested 1520s. Related: Avoided; avoiding.
avoidable (adj.): 1630s, from avoid + -able. Related: Avoidably.
avoidance (n.): late 14c., "action of emptying," from avoid + -ance. Sense of "action of dodging or shunning" is recorded from early 15c.; it also meant "action of making legally invalid," 1620s; "becoming vacant" (of an office, etc.), mid-15c.
avoirdupois (n.): 1650s, misspelling of Middle English avoir-de-peise (c. 1300), from Old French avoir de pois "goods of weight," from aveir "property, goods" (noun use of aveir "have") + peis "weight," from Latin pensum, neuter of pendere "to weigh" (see pendant (n.)). After late 15c., the standard system of weights used in England for all goods except precious metals, precious stones, and medicine.
Avon: river in southwestern England, from Celtic abona "river," from *ab- "water" (see afanc).
avouch (v.): late 15c., from Middle French avochier "call upon as authority," in Old French "call (to court), advocate, plead (a case)," from Latin advocare "call to" as a witness (see advocate).
Avouch, which is no longer in common use, means guarantee, solemnly aver, prove by assertion, maintain the truth or existence of, vouch for .... Avow means own publicly to, make no secret of, not shrink from admitting, acknowledge one's responsibility for .... Vouch is now common only in the phrase vouch for, which has taken the place of avouch in ordinary use, & means pledge one's word for .... [Fowler]
Related: Avouched; avouching.
avow (v.): early 13c., from Anglo-French avouer, Old French avoer "acknowledge, accept, recognize," especially as a protector (Modern French avouer), from Latin advocare (see advocate). A synonym of avouch (q.v.), which tends to contain the more technical, legal aspect of the word. Related: Avowed; avowing.
avowal (n.): 1727, from avow + -al (2).
avuncular (adj.): 1789, from Latin avunculus "maternal uncle," diminutive of avus (see uncle) + -ar. Used humorously for "of a pawnbroker" (uncle was slang for "pawnbroker" from c. 1600 through 19c.).
My only good suit is at present under the avuncular protection. ["Fraser's Magazine," 1832]
aw (interj.): expresion of mild disappointment, sympathy, etc., first recorded in this form by 1888.
AWACS (n.): 1966, initialism (acronym) for "Airborne Warning and Control Systems."
await (v.): mid-13c., awaiten, "to wait for," from Old North French awaitier (Old French agaitier) "to lie in wait for, watch, observe," from a- "to" (see ad-) + waitier "to watch" (see wait (v.)). Originally especially "wait for with hostile intent, wait to ambush or spy upon." Related: Awaited; awaiting.
awake (v.): a merger of two Middle English verbs: 1. awaken, from Old English awæcnan (earlier onwæcnan; strong, past tense awoc, past participle awacen) "to awake, arise, originate," from a "on" + wacan "to arise, become awake" (see wake (v.)); and 2. awakien, from Old English awacian (weak, past participle awacode) "to awaken, revive; arise; originate, spring from," from a "on" (see a (2)) + wacian "to be awake, remain awake, watch" (see watch (v.)).

Both originally were intransitive only; the transitive sense being expressed by Middle English awecchen (from Old English aweccan) until later Middle English. In Modern English, the tendency has been to restrict the strong past tense and past participle (awoke, awoken) to the original intransitive sense and the weak inflection (awakened) to the transitive, but this never has been complete (see wake (v.); also compare awaken).
awake (adj.): "not asleep," c. 1300, shortened from awaken, past participle of Old English awæcnan (see awaken).
awaken (v.): Old English awæcnan (intransitive), "to spring into being, arise, originate," also, less often, "to wake up;" earlier onwæcnan, from a- (1) "on" + wæcnan (see waken). Transitive meaning "to rouse from sleep" is recorded from 1510s; figurative sense of "to stir up, rouse to activity" is from c. 1600.

Originally strong declension (past tense awoc, past participle awacen), already in Old English it was confused with awake (v.) and a weak past tense awæcnede (modern awakened) emerged and has since become the accepted form, with awoke and awoken transferred to awake. Subtle shades of distinction determine the use of awake or awaken in modern English. Related: Awakening.
award (v.): late 14c., "decide after careful observation," from Anglo-French awarder, from Old North French eswarder (Old French esguarder) "decide, examine" (after careful consideration), from es- "out" (see ex-) + warder "to watch" (see ward (n.)). Related: Awarded; awarding.
award (n.): late 14c., "decision after consideration," from Anglo-French award, Old French esguard, from esguarder (see award (v.)). Meaning "something awarded" is first attested 1590s.
aware (adj.): late Old English gewær, from Proto-Germanic *ga-waraz (source also of Old Saxon giwar, Middle Dutch gheware, Old High German giwar, German gewahr), from *ga-, intensive prefix, + waraz "wary, cautious" (see wary).
awareness (n.): 1828, from aware + -ness.
awash (adj.): 1825, originally nautical, "on the level of, flush with," from a- (1) "on" + wash (n.). Figurative use by 1912.
away (adv.): late Old English aweg, earlier on weg "on from this (that) place;" see a- (1) + way (n.). Colloquial use for "without delay" (fire away, also right away) is from earlier sense of "onward in time" (16c.). Intensive use (as in away back) is American English, first attested 1818.
awe (n.): c. 1300, aue, "fear, terror, great reverence," earlier aghe, c. 1200, from a Scandinavian source, such as Old Norse agi "fright;" from Proto-Germanic *agiz- (source also of Old English ege "fear," Old High German agiso "fright, terror," Gothic agis "fear, anguish"), from PIE *agh-es- (source also of Greek akhos "pain, grief"), from root *agh- "to be depressed, be afraid" (see ail). Current sense of "dread mixed with admiration or veneration" is due to biblical use with reference to the Supreme Being. To stand in awe (early 15c.) originally was simply to stand awe. Awe-inspiring is recorded from 1814.
Al engelond of him stod awe.
["The Lay of Havelok the Dane," c. 1300]
awe (v.): c. 1300, from awe (n.); Old English had egan (v.). Related: Awed; awing.
aweigh (adj.): "raised, perpendicular," 1620s, nautical, from a- (1) + weigh.
awesome (adj.): 1590s, "profoundly reverential," from awe (n.) + -some (1). Meaning "inspiring awe" is from 1670s; weakened colloquial sense of "impressive, very good" is recorded by 1961 and was in vogue from after c. 1980. Related: Awesomely; awesomeness.
awestruck (adj.): 1630s, "overwhelmed by reverential fear," from awe (n.) + struck (see strike (v.)).
awful (adj.): c. 1300, agheful "worthy of respect or fear," from aghe, an earlier form of awe (n.), + -ful. The Old English word was egefull. Weakened sense "very bad" is from 1809; weakened sense of "exceedingly" is by 1818.
awfully (adv.): c. 1300, "so as to inspire reverence," from awful + -ly (2). Meaning "dreadfully, so as to strike one with awe" is recorded from late 14c. As a simple intensifier, "very, exceedingly," is attested from c. 1830.
awhile (adv.): Old English ane hwile "(for) a while" (see while (n.)); usually written as one word since 13c.
awhirl (adj.): 1837, from a- (1) + whirl (v.).
awing (n.): "action of inspiring with awe," 1650s, verbal noun from awe (v.).
awk (adj.): mid-15c., "turned the wrong way," from Old Norse afugr "turned backwards, wrong, contrary," from Proto-Germanic *afug-, from PIE *apu-ko-, from root *apo- "off, away" (see apo-). Obsolete since 17c.
awkward (adj.): mid-14c., "in the wrong direction," from awk "back-handed" + adverbial suffix -weard (see -ward). Meaning "clumsy" first recorded 1520s. Related: Awkwardly. Other formations from awk, none of them surviving, were awky, awkly, awkness.
awkwardness (n.): 1704, "lack of grace," from awkward + -ness. Meaning "physical clumsiness" is attested from c. 1770; that of "social embarrassment" is from 1788.
awl (n.): Old English æl "awl, piercer," from Proto-Germanic *ælo (source also of Old Norse alr, Dutch aal, Middle Low German al, Old High German äla, German Ahle), which is of uncertain origin. Earliest references are to piercing of the ears, though later it was associated with shoemakers. Through misdivision, frequently written 15c.-17c. as nawl (for an awl; see N).
awn (n.): "bristly fibers on grain of plants," c. 1300, from Old Norse ögn, from Proto-Germanic *agano (source also of Old English egenu, Old High German agana, German Ahne, Gothic ahana), from PIE *ak-ona- (source also of Sanskrit asani- "arrowhead," Greek akhne "husk of wheat," Latin acus "chaff," Lithuanian akuotas "beard, awn"); suffixed form of PIE root *ak- "sharp" (see acrid).
awning (n.): 1624, origin uncertain (first recorded use is by Capt. John Smith), perhaps from Middle French auvans, plural of auvent "a sloping roof," "itself of doubtful etym[ology]" (OED). A nautical term only until sense of "cover for windows or porch" emerged 1852.
awoke: past tense of awake (v.), from Old English awoc; also see awaken. The tendency has been to restrict the strong past tense (awoke) to the original intransitive sense of awake and the weak inflection (awakened) to the transitive, but this never has been complete.
awoken: past participle of awake (v.); also see awaken. The tendency has been to restrict the strong past participle (awoken) to the original intransitive sense of awake and the weak inflection (awakened) to the transitive, but this never has been complete.
awol (adj.): also a.w.o.l., military initialism (acronym) for absent without leave. The -o- seems to be there mostly so the assemblage can be pronounced as a word. In U.S. military use at least from World War II, popular use by 1960.
awry (adv.): late 14c., "crooked, askew," from a- (1) "on" + wry (adj.).