Online Etymology Dictionary

twice (adv.): late Old English twies, from Old English twiga, twigea "two times," from Proto-Germanic *twiyes (source also of Old Frisian twia, Old Saxon tuuio), from PIE *dwis-, adverbial form of *dwo- "two" (see two). Spelling with -ce reflects the voiceless pronunciation.
Life is as tedious as a twice-told tale
Vexing the dull ear of a drowsy man.
["King John," III.iv.]
Think twice, then speak was an "old Prouerbe" by 1623. At twice, though less common than at once, means "at two distinct times; by two distinct operations."
twiddle (v.): 1540s, "to trifle," of unknown origin, said to be probably imitative; of the fingers, "to twirl idly," first recorded 1670s. Figurative phrase twiddle one's thumbs "have nothing to do" is recorded from 1846; to twirl one's thumbs in the same sense is recorded from 1816. Related: Twiddled; twiddling.
twig (n.): Old English twig "twig, branch, shoot, small tree," from Proto-Germanic *twigga "a fork" (source also of Middle Dutch twijch, Dutch twijg, Old High German zwig, German Zweig "branch, twig"), from PIE *dwi-ko-, from *dwo- "two" (see two). Compare Old English twisel "fork, point of division."
twiggy (adj.): "slender," 1560s, from twig + -y (2). The famous 1960s English model was born Lesley Hornby (1949). The older adjectival form was twiggen "made of twigs" (1540s).
twilight (n.): "light from the sky when the sun is below the horizon at morning and evening," late 14c. (twilighting), a compound of twi- + light (n.) Cognate with Middle Flemish twilicht, Dutch tweelicht (16c.), Middle High German twelicht, German zwielicht. Exact connotation of twi- in this word is unclear, but it appears to refer to "half" light, rather than the fact that twilight occurs twice a day. Compare also Sanskrit samdhya "twilight," literally "a holding together, junction," Middle High German zwischerliecht, literally "tweenlight." Originally and most commonly in English with reference to evening twilight but occasionally used of morning twilight (a sense first attested mid-15c.). Figurative extension recorded from c. 1600.

Twilight zone is from 1901 in a literal sense, a part of the sky lit by twilight; from 1909 in extended senses in references to topics or cases where authority or behavior is unclear. In the 1909 novel "In the Twilight Zone," the reference is to mulatto heritage. "She was in the twilight zone between the races where each might claim her ...." The U.S. TV series of that name is from 1959.
twill (n.): "cloth woven in parallel diagonal lines," early 14c., Scottish and northern English variant of Middle English twile, from Old English twili "woven with double thread, twilled," partial loan-translation of Latin bilix "with a double thread" (with Old English twi- substituted for cognate Latin bi-); the second element from Latin licium "thread," which is of uncertain origin.
twin (adj.): Old English twinn "consisting of two, twofold, double, two-by-two," from Proto-Germanic *twisnjaz "double" (source also of Old Norse tvinnr "double, twin," Old Danish tvinling, Dutch tweeling, German zwillung), from PIE *dwisno- (source also of Latin bini "two each," Lithuanian dvynu "twins"), from *dwi- "double," from root *dwo- "two" (see two). Minneapolis and St. Paul in Minnesota have been the Twin Cities since 1883, but the phrase was used earlier of Rock Island and Davenport (1856).
twin (v.): "to combine two things closely, join, couple," late 14c., from twin (adj.). Related: Twinned; twinning. In Middle English, the verb earlier and typically meant "to part, part with, separate from, estrange," etc. (c. 1200), on the notion of making two what was one.
twin (n.): c. 1300, from Old English getwinn "double;" getwinnas "twins, two born at one birth," from twinn (see twin (adj.)).
twine (n.): "strong thread made from twisted strands," Old English twin "double thread," from Proto-Germanic *twiznaz "double thread, twisted thread" (source also of Dutch twijn, Low German twern, German zwirn "twine, thread"), from the same root as twin (adj.).
twine (v.): "to twist strands together to form twine," c. 1300, from twine (n.) and probably also from Old Norse tvinna "to double." Sense of "to twist around something" (as twine does) is recorded from late 14c. Related: Twined; twining.
twinge (n.): 1540s, "a pinch, a nipping," from obsolete verb twinge "to pinch, tweak," from Old English twengan "to pinch," from Proto-Germanic *twangjan (source also of Old Frisian thwinga, Old Norse þvinga, Danish tvinge, Dutch dwingen, Old High German thwingan, German zwingen "to compel, force"), from PIE *twengh- "to press in on" (see thong). Meaning "sharp, sudden minor pain" is recorded from c. 1600. Figurative sense (with reference to shame, remorse, etc.) is recorded from 1620s.
twink (n.): c. 1400, in phrase in a twynk of oon eye "suddenly, almost instantaneously," from twink (v.) "to wink," probably from Old English twincan (see twinkle (v.)). Meaning "a twinkle" is from 1830. Meaning "young sexually attractive person" is recorded from 1963, probably from Twinkie; but compare 1920s-30s British homosexual slang twank in a similar sense.
Twinkie (n.): snack food, supposedly invented and named 1930 by Jimmy Dewar, baker for the Chicago branch of Continental Baking Co. (later Hostess); said to have been inspired by twinkle.
twinkle (v.): Old English twinclian "to twinkle, wink," frequentative of twincan "to wink, blink," with -el (3). Twincan is related to Middle High German zwinken, German zwinkern, and probably somehow imitative. Related: Twinkled; twinkling. The noun is recorded from 1540s. Phrase in the twinkling of an eye "in a very brief time" is attested from c. 1300.
twirl (v.): 1590s, "move round rapidly" (intransitive), of uncertain origin, possibly connected with Old English þwirl "a stirrer, handle of a churn," and Old Norse þvara "pot-sticker, stirrer." Or on another guess a blend of twist and whirl. Transitive sense, "cause to revolve rapidly," is from 1620s. Related: Twirled; twirling.
twirl (n.): 1590s, "rapid circular motion," from twirl (v.).
twirler (n.): 1808, agent noun from twirl (v.). As baseball slang for "pitcher," by 1891.
twist (n.): mid-14c., "flat part of a hinge" (now obsolete), probably from Old English -twist "divided object; fork; rope" (as in mæsttwist "mast rope, stay;" candeltwist "wick"), from Proto-Germanic *twis-, from PIE root *dwo- (see two). Original senses suggest "dividing in two" (source also of cognate Old Norse tvistra "to divide, separate," Gothic twis- "in two, asunder," Dutch twist, German zwist "quarrel, discord," though these senses have no equivalent in English), but later ones are of "combining two into one," hence the original sense of the word may be "rope made of two strands."

Meaning "thread or cord composed of two or more fibers" is recorded from 1550s. Meaning "act or action of turning on an axis" is attested from 1570s. Sense of "beverage consisting of two or more liquors" is first attested c. 1700. Meaning "thick cord of tobacco" is from 1791. Meaning "curled piece of lemon, etc., used to flavor a drink" is recorded from 1958. Sense of "unexpected plot development" is from 1941.

The popular rock 'n' roll dance craze is from 1961, so called from the motion involved, but twist was used to describe popular dances in 1894 and again in the 1920s. To get one's knickers in a twist "be unduly agitated" is British slang first attested 1971.
twist (v.): c. 1200 (implied in past tense form twaste), "to wring," from twist (n.). Sense of "to spin two or more strands of yarn into thread" is attested from late 15c. Meaning "to move in a winding fashion" is recorded from 1630s. To twist the lion's tail was U.S. slang (1895) for "to provoke British feeling" (the lion being the symbol of Britain). To twist (someone's) arm in the figurative sense of "pressure (to do something)" is from 1945. Related: Twisted; twisting.
twist-off (adj.): of bottle or jar caps, 1959, from the verbal phrase; see twist (v.) + off (adv.).
twisted (adj.): late 15c., "intertwined, past participle adjective from twist (v.). Meaning "perverted, mentally strange" (1900) probably is from twist (n.) in a sense of "mental peculiarity, perversion" attested by 1811.
twister (n.): late 15c., "one who spins thread," agent noun from twist (v.). Meaning "tornado" is attested from 1881, American English.
twisty (adj.): 1857, "full of windings," from twist (n.) + -y (2). Meaning "attractively feminine," 1970s slang, is from twist "girl" (1928), apparently from rhyming slang twist and twirl (1924).
twit (v.): "to blame, reproach, taunt, upbraid," 1520s, twite, shortened form of Middle English atwite, from Old English ætwitan "to blame, reproach," from æt "at" + witan "to blame," from Proto-Germanic *witanan "to look after, guard, ascribe to, reproach" (source also of Old English wite, Old Saxon witi, Old Norse viti "punishment, torture;" Old High German wizzi "punishment," wizan "to punish;" Dutch verwijten, Old High German firwizan, German verweisen "to reproach, reprove," Gothic fraweitan "to avenge"), from PIE root *weid- "to see" (see vision). For sense evolution, compare Latin animadvertere, literally "to give heed to, observe," later "to chastise, censure, punish." Related: Twitted; twitting. As a noun meaning "a taunt" from 1520s.
twit (n.): "foolish, stupid and ineffectual person," 1934, British slang, popular 1950s-60s, crossed over to U.S. with British sitcoms. It probably developed from twit (v.) in the sense of "reproach," but it may be influenced by nitwit.
twitch (v.): late 12c., to-twic-chen "pull apart with a quick jerk," related to Old English twiccian "to pluck, gather, catch hold of," from Proto-Germanic *twikjon- (source also of Low German twicken, Dutch twikken, Old High German gizwickan, German zwicken "to pinch, tweak"). Related: Twitched; twitching.
twitch (n.): 1520s, from twitch (v.).
twitter (v.): late 14c., twiteren, in reference to birds, of imitative origin (compare Old High German zwizziron, German zwitschern, Danish kvidre, Old Swedish kvitra). The noun meaning "condition of tremulous excitement" is attested from 1670s. The microblogging service with the 140-character limit was introduced in 2006. The following is considered an unrelated word of obscure origin:
TWITTER. 1. "That part of a thread that is spun too small." Yarn is said to be twined to twitters, when twined too small, S. Hence, to twitter yarn, to spin it unequally, A. Bor. Ray.
2. It is transferred to any person or thing that is slender or feeble. It is said of a lank delicate girl: "She is a mere twitter," S. [Jamieson, "Etymological Dictionary of the Scottish Language," Edinburgh, 1808]
twitterpated (adj.): 1942, apparently first attested in the Walt Disney movie "Bambi" (there also was a song by that name but it was not in the studio release of the film), a past participle adjective formed from twitter in the "tremulous excitement" noun sense (1670s) + pate (n.2) "head" (compare flutterpated, 1894).
Thumper: Why are they acting that way?
Friend Owl: Why, don't you know? They're twitterpated.
Flower, Bambi, Thumper: Twitterpated?
Friend Owl: Yes. Nearly everybody gets twitterpated in the springtime. For example: You're walking along, minding your own business. You're looking neither to the left, nor to the right, when all of a sudden you run smack into a pretty face. Woo-woo! You begin to get weak in the knees. Your head's in a whirl. And then you feel light as a feather, and before you know it, you're walking on air. And then you know what? You're knocked for a loop, and you completely lose your head!
Thumper: Gosh, that's awful.
twizzle (v.): "to twist, form by twisting" (transitive), 1788, apparently a made-up word suggested by twist. Related: Twizzled; twizzling.
two (adj.): Old English twa "two," fem. and neuter form of twegen "two" (see twain), from Proto-Germanic *twa (source also of Old Saxon and Old Frisian twene, twa, Old Norse tveir, tvau, Dutch twee, Old High German zwene, zwo, German zwei, Gothic twai), from PIE *duwo, variant of dwo "two" (source also of Sanskrit dvau, Avestan dva, Greek duo, Latin duo, Old Welsh dou, Lithuanian dvi, Old Church Slavonic duva "two," first element in Hittite ta-ugash "two years old").

Two-fisted is from 1774. Two cheers for _____, expressing qualified enthusiasm first recorded 1951 in E.M. Forster's title "Two Cheers for Democracy." Two-dimensional is recorded from 1883; figurative sense of "lacking substance or depth" is attested from 1934.
two bits (n.): "quarter dollar," 1730, in reference to the Mexican real, a large coin that was divided into eight bits; see bit (n.1). Compare piece of eight (see piece (n.)). Two bits thus would have equaled a quarter of the coin. Hence two-bit (adj.) "cheap, tawdry," first recorded 1929.
two-faced (adj.): also two faced, "deceitful," 1610s; see two + face (n.).
two-step (n.): dance style, 1893, from two + step (n.); so called for the time signature of the music (as distinguished from the three-step waltz). But as the positions taken by the dancers involved direct contact, it was highly scandalous in its day and enormously popular.
A certain Division of an Auxiliary gave a dance not long since. I went and looked on. What did they dance? Two-step, two-step and two-step. How did they dance? When we used to waltz, we clasped arms easily, took a nice, respectable position, and danced in a poetry of motion. Now, girls, how do you two-step? In nine cases out of ten the dear girl reposes her head on the young man's shoulder, or else their faces press each other. He presses her to his breast as closely as possible, and actually carries her around. Disgraceful? I should say so. Do you wonder at the ministers preaching on dancing as a sin, when it looks like this to a woman like myself who believes in dancing and has danced all her life? Mothers, as you love your girls, forbid them to dance after this manner. [letter in the ladies' section of "Locomotive Engineers' Monthly Journal," March 1898]

To the Two Step may be accredited, serious injury to the Waltz, awkward and immodest positions assumed in round dancing, also as being a prominent factor in overcrowding the profession and causing a general depression in the business of the legitimate Master of Dancing. ["The Director," March 1898]
two-time (v.): "to deceive, cheat, betray," 1924, perhaps from notion of "to have two at a time." An earlier reference (1922) in a Kentucky criminal case involves a double-cross or betrayal without a romance angle. Related: two-timing (adj.); two-timer.
twofer (n.): 1911 (originally in reference to cigars), from two for (a quarter); see two + for.
twofold (adj.): Old English tweofeald; see two + -fold.
Tyburn: place of public execution for Middlesex from c. 1200 to 1783; it stood at the junction of modern Oxford Street, Bayswater Road and Edgware Road.
Tyche: goddess of fortune, Latinized form of Greek Tykhe, literally "fortune."
tycoon (n.): 1857, title given by foreigners to the shogun of Japan (said to have been used by his supporters when addressing foreigners, as an attempt to convey that the shogun was more important than the emperor), from Japanese taikun "great lord or prince," from Chinese tai "great" + kiun "lord." Transferred meaning "important person" is attested from 1861, in reference to U.S. president Abraham Lincoln (in the diary of his secretary, John Hay); specific application to "wealthy and powerful businessman" is post-World War I.
tyke (n.): late 14c., "cur, mongrel," from a Scandinavian source akin to Old Norse tik "bitch," from Proto-Germanic *tikk- (source also of Middle Low German tike). Also applied in Middle English to a low-bred or lazy man. The meaning "child" is from 1902, though the word was used in playful reproof from 1894. As a nickname for a Yorkshireman, from c. 1700; "Perhaps originally opprobrious; but now accepted and owned" [OED].
Tylenol (n.): introduced 1955 as the name of an elixir for children, trade name originally registered by McNeil Laboratories, Philadelphia, Pa., from elements abstracted from N-acetyl-para-aminophenol, the chemical name of its active compound.
Tyler: surname, 12c., literally "tile-maker."
tympanic (adj.): 1808, from tympanum + -ic.
tympanist (n.): 1610s, "one who plays on a drum," from Latin tympanista, from Greek tympanistes, from tympanizein, from tympanon (see tympanum). Since mid-19c. specifically of players on kettledrums.
tympanum (n.): "drum of the ear," 1610s, from Medieval Latin tympanum, introduced in this sense by Italian anatomist Gabriello Fallopio (1523-1562), from Latin tympanum "a drum, timbrel, tambourine," from Greek tympanon "a kettledrum," from root of typtein "to beat, strike" (see type (n.)). Compare Old English timpan "drum, timbrel, tambourine," from Latin tympanum. The modern meaning "a drum" is attested in English from 1670s.
type (n.): late 15c., "symbol, emblem," from Latin typus "figure, image, form, kind," from Greek typos "a blow, dent, impression, mark, effect of a blow; figure in relief, image, statue; anything wrought of metal or stone; general form, character; outline, sketch," from root of typtein "to strike, beat," from PIE *tup-, variant of root *(s)teu- (1) "to push, stick, knock, beat" (see steep (adj.)).

Extended 1713 to printing blocks with letters carved on them in relief. The meaning "general form or character of some kind, class" is attested in English from 1843, though it had that sense in Latin and Greek. To be (someone's) type "be the sort of person that person is attracted to" is recorded from 1934.
type (v.): "to write with a typewriter," 1888; see type (n.). Earlier it meant "to symbolize, typify" (1836) and "to foreshadow" (1590s). Related: Typed; typing.
type-setting (n.): 1824, from type (n.) in the printing sense + verbal noun from set (v.).