Online Etymology Dictionary

dither: 1649, "to quake, tremble," phonetic variant of M.E. didderen (c.1375), of uncertain origin. The sense of "vacillate, be anxious" is from 1819.
dithyramb: 1603, from L. dithyrambus, from Gk. dithyrambos, of unknown origin, perhaps a pre-Hellenic loan-word. A wild choric hymn, originally in honor of Dionysus.
ditto: 1625, Tuscan dial. ditto "(in) the said (month or year)," from It. detto, pp. of dire "to say," from L. dicere (see diction). Originally used in It. to avoid repetition of month names in a series of dates; generalized meaning of "same as above" first recorded in Eng. 1678.
ditty: c.1300, from O.Fr. ditie "composition, poem, treatise," from L. dictatum "thing dictated," neut. pp. of dictare "dictate." Ditty bag is 1850s nautical slang, perhaps from Brit. naval phrase commodity bag.
ditzy: "stupid, scatterbrained" (esp. of women), late 1970s U.S. slang, of unknown origin, perhaps related to earlier slang dicty (1926) "conceited, snobbish," also of unknown origin. The noun ditz (1984) is a back-formation.
diuretic: c.1400, from O.Fr. diuretique, from L.L. diureticus, from Gk. diouretikos "prompting urine," from diourein "urinate," from dia "through" + ourein "urine."
diurnal: c.1390, from L.L. diurnalis, from diurnum "day," from L. diurnus "daily," from dies "day" + -urnus, an adj. suffix denoting time (cf. hibernus "wintery"). Dies "day" is from PIE base *dyeu- (cf. Skt. diva "by day," Welsh diw, Bret. deiz "day;" Arm. tiw; Lith. diena; O.C.S. dini, Pol. dzien, Rus. den), lit. "to shine" (cf. Gk. delos "clear;" L. deus, Skt. deva "god," lit. "shining one;" Avestan dava- "spirit, demon;" Lith. devas, O.N. tivar "gods;" O.E. Tig, gen. Tiwes, see Tuesday).
diva: "distinguished woman singer," 1883, from It. diva "goddess, fine lady," from L. diva "goddess," fem. of divus "divine (one)."
divan: 1586, "Oriental council of state," from Turk. divan, from Arabic diwan, from Pers. devan "bundle of written sheets, small book, collection of poems" (as in the "Divan i-Hafiz"), related to debir "writer." Sense evolved through "book of accounts," to "office of accounts," "custom house," "council chamber," then to "long, cushioned seat," such as are found along the walls in Middle Eastern council chambers. (See couch.) The sofa/couch sense was taken into Eng. 1702; the "book of poems" sense in 1823.
dive: emerged 13c. from O.E. dufan "to dive, duck, sink" (intransitive, class II strong verb; past tense deaf, pp. dofen) and dyfan "to dip, submerge" (weak, transitive), from P.Gmc. *dubijanan. Past tense dove is a later formation, perhaps on analogy of drive/drove. Sense of "disreputable bar" is first recorded Amer.Eng. 1871, perhaps because they were usually in basements, and going into one was both a literal and fig. "diving."
diverge: 1665, from L. divergere "go in different directions," from dis- "apart" + vergere "to bend, turn" (see verge (v.)). Originally a term in optics; the fig. sense is 19c.
divers (adj.): c.1275, "various," from O.Fr. divers "different or odd," from L. diversus "turned different ways," in L.L. "various," pp. of divertere (see divert). Sense of "several, numerous" is recorded from 1297, referring "originally and in form to the variety of objects; but, as variety implies number, becoming an indeffinite numeral word expressing multiplicity" [OED].
diverse: 1297, spelling variant of divers (q.v.), perhaps by analogy with converse, traverse, etc. More associated with L. diversus, and since c.1700 restricted to the meaning "different in character or quality." Diversification in the economic sense is from 1939. Diversity is c.1340.
diversion: 1600, from M.Fr. diversion, from L.L. diversionem (nom. diversio), from L. divertere (see divert). Sense of "amusement, entertainment" is first recorded 1648. Hence, divertimento (1823), from the It. form, originally "a musical composition designed primarily for entertainment."
divert: 1430, from M.Fr. divertir, from L. divertere "in different directions," blended with devertere "turn aside," from dis- "aside" and de- "from" + vertere "to turn" (see versus).
diverticulum: "blind tube" (anatomical), 1819, Mod.L., from L. deverticulum "a bypath," from devertere "to turn aside" (see divert).
Dives: traditional name for a rich man, c.1386, from L. dives "rich (man)," used in Luke xvi in Vulgate and commonly mistaken as the proper name of the man in the parable. Related to divus "divine," and originally meaning "favored by the gods."
divest: 1563, from M.Fr. devester "strip of possessions," from O.Fr. desvestir, from des- "away" + vestir "to clothe." The fig. sense of "strip of possessions" is earliest in Eng.; reflexive sense of "to strip oneself of" is from 1605. Economic sense (implied in divestment) is from 1955.
divide (v.): c.1374, from L. dividere "to force apart, cleave, distribute," from dis- "apart" + -videre "to separate," from PIE base *widh- "to separate," related to widow; and see with. Mathematical sense is from c.1425. The noun meaning "watershed, separation between river valleys" is first recorded 1807. Divider "partition or screen," especially in a room, is from 1959. Divide and rule (1602) translates L. divide et impera, a maxim of Machiavelli.
dividend: c.1477, from M.Fr. dividende "a number divided by another," from L. dividendum "thing to be divided," neut. gerundive of dividere (see divide). Sense of "portion of interest on a loan, stock, etc." is from 1690.
divine (adj.): c.1305 (implied in divinity), from O.Fr. devin, from L. divinus "of a god," from divus "a god," related to deus "god, deity," from PIE *deiwos, also the root of words for "sky" and "day." The god-sense is originally "shining," but "whether as originally sun-god or as lightener" is not now clear. Weakened sense of "excellent" had evolved by c.1470. Divinity is from c.1300.
divine (v.): "to conjure, to guess," originally "to make out by supernatural insight," early 14c., from L. divinus (see divine (adj.)), which also meant "soothsayer." Hence, divination (c.1374), from O.Fr., from L. divinationem (nom. divinatio) "the power of foreseeing, prediction," from divinatus, pp. of divinare, lit. "to be inspired by a god." Divining rod (or wand) attested from 1656.
division: c.1374, from O.Fr. division, from L. divisionem (nom. divisio), from divid-, stem of dividere (see divide). Military sense is first recorded 1597. Mathematical sense is from c.1425. The mathematical division sign supposedly was invented by British mathematician John Pell (1611-85) who taught at Cambridge and Amsterdam. Divisive "producing discord" is from 1642.
divorce: 1377, from O.Fr. divorce, from L. divortium "separation, dissolution of marriage," from divertere "to separate, leave one's husband, turn aside" (see divert). Not distinguished in Eng. from legal separation until mid-19c. Divorcee, from Fr., first recorded 1813. It can be either m. or f.
divot: 1536, from Scot., lit. "piece of turf or sod" used for roofing material, etc., of unknown origin. The golfing sense is from 1886.
divulge: 1460, from L. divulgare "publish, make common," from dis- "apart" + vulgare "make common property," from vulgus "common people."
divvy: 1872, probably a slang alteration of divide.
Dixie: 1859, first attested in D.D. Emmett's song of that name, probably a reference to the Mason-Dixon Line, but there are many other well-publicized theories. Popularized nationwide in minstrel shows. Dixieland style of jazz developed in New Orleans c.1910, so called from 1919. Dixiecrat in U.S. politics dates from 1948.
dizzy: O.E. dysig "foolish, stupid," from P.Gmc. *dusijaz. Meaning "having a whirling sensation" is from c.1340; that of "giddy" is from 1501 and seems to merge the two earlier meanings. Used of the "foolish virgins" in early translations of Matthew xxv; used especially of blondes since 1870s.
diæresis: 1611, "sign marking the division of a diphthong into two simple sounds," from L. diæresis, from Gk. diairesis, noun of action from diairein "to divide, separate."
DNA: 1944 abbreviation of deoxyribonucleic acid (1931).
do: M.E. do, first person singular of O.E. don, from W.Gmc. *don, from PIE base *dhe- "to put, place, do, make" (see factitious). Slang meaning "to do the sex act with or to" is from 1913. Second person does was a Northumbrian variant in O.E. that displaced doth, doeth 16c.-17c. The pt. did is O.E. dyde, the only remainder in Gmc. of the old linguistic pattern of forming a pt. by reduplication of the stem of the present tense. Far back in Gmc. the equivalent of did was used as a suffix to make the past tenses of other verbs, hence the English -ed suffix (O.E. -de). The pp. done grew out of O.E. pp. gedon, but the only vestige of the prefix is in ado. Periphrastic form in negative sentences ("They did not think") replaced the O.E. negative particles ("Hie ne wendon"). U.S. Southern use of done in phrases like "he done gone to the store" is attested from 1827, according to OED: "a perfective auxiliary or with adverbial force in the sense 'already; completely.' " Slang done for "doomed" is from 1842. Doable has been around since 1449. Expression do or die is attested from 1621. Contraction don't for do not is first recorded 1672.
do-gooder: "a person who seeks to correct social ills in an idealistic, but usually impractical or superficial, way," 1654 (as do-good), in "Zootomia, or Observations on the Present Manners of the English: Briefly Anatomizing the Living by the Dead. With An Usefull Detection of the Mountebanks of Both Sexes," written by Richard Whitlock, a medical doctor. Probably used even then with a taint of impractical idealism. Modern pejorative use seems to have begun on the socialist left, mocking those who were unwilling to take a hard line. OED has this citation, from "The Nation" in 1923:
"There is nothing the matter with the United States except ... the parlor socialists, up-lifters, and do-goods."
The form do-gooder appears in Amer.Eng. from 1927, presumably because do-good was no longer felt as sufficiently noun-like. A slightly older word for this was goo-goo.
do-si-do: 1929, from Fr. dos-à-dos "back to back."
dobbie: "household sprite," 1811, from playful use of the proper name represented in dobbin (q.v.). In Sussex, such apparitions were called Master Dobbs.
dobbin: "farm horse," 1596 (in "Merchant of Venice"), probably from diminutive form of Dob, familiar of Robin; personal name applied to a horse.
Dobermann pinscher: 1917, for Ludwig Dobermann, 19c. Ger. dog-breeder in Thuringia.
dobro: 1952, Amer.Eng., from the name of its Czech-born inventors, Dopera Brothers. The word also happens to mean "good thing" in Czech. Patent filed 1947, claims use from 1929.
docent: 1639, from L. docentem, from docere "to teach" (see doctor).
Docetism: 1846, heresy holding that the body of Jesus was a phantom, from Gk. Doketai, name of the sect, lit. "believers," from dokein "to seem, have the appearance of, think," related to doxa (see decent).
docile: 1483, from It. or Fr. docile, from L. docilis "easily taught," from docere "teach" (see doctor). Sense of "obedient, submissive" first recorded 1774.
docimacy: "judicial inquiry into the character of aspirants for office or citizenship," especially in ancient Athens, 1801, from Gk. dokimasia "assay, proving, examination," from stem of dokimazein "to test, prove," from dokimos "proven, genuine," lit. "accepted," related to dekhesthai "to take, accept," cognate with L. decere "to be seemly or fitting" (see decent).
dock (n.1): "ship's berth," 1486, from M.Du. or M.L.G. docke, perhaps ultimately (via L.L. *ductia "aqueduct") from L. ducere "to lead" (see duke); or possibly from a Scand. word for "low ground" (cf. Norw. dokk "hollow, low ground"). Original sense was "furrow a grounded vessel makes in a mud bank."
dock (n.2): "where accused stands in court," 1586, originally rogue's slang, from Flem. dok "pen or cage for animals," origin unknown.
dock (v.): "cut an animal's tail," c.1386, from dok (n.) "fleshy part of an animal's tail," related to O.E. -docca "muscle," from P.Gmc. *dokko "something round, bundle" (cf. O.N. dokka "bundle, girl," Dan. dukke "doll," Ger. Docke "small column, bundle, doll, smart girl"). Meaning "to reduce (someone's) pay for some infraction" is first recorded 1822.
docket: c.1460, "a summary or abstract," of unknown origin, perhaps a dim. form related to dock (v.). An early form was doggette.
doctor: c.1303, "Church father," from O.Fr. doctour, from M.L. doctor "religious teacher, adviser, scholar," from L. doctor "teacher," from doct- stem of docere "to show, teach," originally "make to appear right," causative of decere "be seemly, fitting" (see decent). Familiar form doc first recorded c.1850. Meaning of "holder of highest degree in university" is first found c.1375; that of "medical professional" dates from 1377, though this was not common till late 16c. Verb sense of "alter, disguise, falsify" is first recorded 1774.
Doctor Martens: type of heavy walking boots, 1977 (use claimed from 1965), trademark name taken out by Herbert Funck and Klaus Martens.
doctrine: c.1380, from O.Fr. doctrine (12c.), from L. doctrina "teaching, body of teachings, learning," from doctor "teacher" (see doctor). The Monroe Doctrine in U.S. history was first used 1848, in reference to principles of policy contained in the message of President Monroe to Congress on Dec. 2, 1823. Doctrinaire "one who tries to apply some doctrine without regard for practicality" was borrowed from Fr. 1820; in France, originally of those who tried to reconcile liberty with royal authority after 1815; the broader sense in Eng. is attested from 1831.
document: c.1450, "teaching, instruction," from M.Fr. document "lesson, written evidence," from L. documentum "example, proof, lesson," in M.L. "official written instrument," from docere "to show, teach" (see doctor). Meaning "something written that provides proof or evidence" is from 1727; the verb meaning "to support by documentary evidence" is from 1711. Documentary first used 1930 in sense of "film based on actual events," from Fr. film documentarie (1924). Docudrama is a 1961 coinage.