A- (3) prefix meaning "not," from Gk a-, an- "not," from pie base *ne "not" (see un-)

deluge (n.) --- c.1374, from O.Fr. deluge (12c.), earlier deluve, from L. diluvium, from diluere "wash away," from dis- "away" + -luere, comb. form of lavere "to wash" (see lave). The verb is from 1649.

delusion --- act of misleading someone, c.1420; as a form of mental derangement, 1552. See delude. Technically, delusion is a belief that, though false, has been surrendered to and accepted by the whole mind as a truth; illusion is an impression that, though false, is entertained provisionally on the recommendation of the senses or the imagination, but awaits full acceptance and may not influence action. Delusions of grandeur attested from 1909.

deluxe --- 1819, from Fr. de luxe, lit. "of luxury," from L. luxus "excess, abundance."

delve --- O.E. delfan "to dig" (class III strong verb; past tense dealf, pp. dolfen), common W.Gmc. verb with cognates in Slavic. Weak inflections emerged 14c.-16c.

demagogue --- 1648, from Gk. demagogos "leader of the people," from demos "people" (see demotic) + agogos "leader," from agein "to lead" (see act). A term of disparagement ever since it was first used in Athens, 5c. B.C.E.

demand --- c.1290, from O.Fr. demander "to request," from L. demandare "entrust, charge with a commission," from de- "completely" + mandare "to order." The political economy sense (correlating to supply) is first attested 1776 in Adam Smith.

demarcation --- c.1752, from Sp. linea de demarcacion, or Port. linha de demarcaçao, line laid down by the Pope, May 4, 1493, dividing the New World between Spain and Portugal on a line 100 leagues west of the Cape Verde Islands. Applied from 1801 to other lines dividing regions.

demean --- lower in dignity, 1601, perhaps from de- "down" + mean (adj.) and modeled on debase. Indistinguishable in some uses from obsolete demean (see demeanor) which influenced it and may be its true source.

demeanor --- 1494, from obsolete M.E. demean "behave in a certain way" (c.1315), from O.Fr. demener, from de- "completely" + mener "to lead, direct," from L. minare "to threaten," in L.L. "to drive (a herd of animals)." Sense in Eng. evolved from notion of "conduct, manage" (oneself).

demented --- 1644, from obsolete dement "drive mad" (1545), probably from M.Fr. dementer, from L.L. dementare "out of one's mind," from phrase de mente, from de + mente, abl. of mens mind." Dementia is attested from 1806; earlier form in Eng. was demency (1858), from Fr. démence. Dementia præcox is a Mod.L. form recorded from 1899 in Eng., 1891 in Ger., from Fr. démence précoce (1857). See precocious.

demerit --- 1399, from O.Fr. desmerite, from des- "not, opposite" + merite "merit." L. demereri meant "to merit, deserve," from de- in its completive sense. But M.L. demeritum meant "fault." Both senses existed in the M.Fr. form of the word. Meaning "penalty point in school" is attested from 1862.

demesne --- 1292, from O.Fr. demeine, from L. dominicus "belonging to a master," from dominus "lord." Re-spelled by Anglo-Fr. legal scribes under infl. of O.Fr. mesnie "household" (and the concept of a demesne as "land attached to a mansion") and their fondness for inserting -s- before -n-. Essentially the same word as domain.

Demeter --- Gk. Damater, lit. "Earth-Mother," from da, Doric form of Gk. ge "earth" + mater. The name Demetrius means "son of Demeter."

demi- --- early 15c., from O.Fr. demi "half," from L.L. dimedius, from L. dimidius, from dis- "apart" + medius "middle" (see medial).

demigod --- 1530, from demi- + god, rendering L. semideus. The child of sexual intercourse between a deity and a mortal, a man raised to divine rank, or a minor god.

demijohn --- 1769, partial translation and word-play from Fr. damejeanne (1694) "Lady Jane," term used for large globular wicker-wrapped bottle, perhaps because its shape suggested a stout woman in the costume of the period. A general Mediterranean word, with forms found in Sp., Port., It., and Ar.

demilitarize --- 1883, in reference to the Austrian military frontier in the Balkans.

demi-monde --- 1855, from Fr. demi-monde "so-so society," lit. "half-world," from demi- "half" + monde, from L. mundus "world." Popularized by use in title of a comedy by Alexandre Dumas fils. Dumas' Demi-Monde "is the link between good and bad society ... the world of compromised women, a social limbo, the inmates of which ... are perpetually struggling to emerge into the paradise of honest and respectable ladies" ["Fraser's Magazine," 1855]. Not properly used of courtesans. 18c. Eng. demi-rep (1749, the second element short for reputation) was defined as "a woman that intrigues with every man she likes, under the name and appearance of virtue ... in short, whom every body knows to be what no body calls her" [Fielding].

demise --- 1442, from M.Fr. demise, fem. pp. of demettre "dismiss, put away," from des- "away" (from L. dis-) + M.Fr. mettre "put," from L. mittere "let go, send." Originally "transfer of estate by will," meaning extended 1754 to "death" because that's when this happens.

demi-tasse --- 1842, from Fr., lit. "half-cup," from demi- + tasse, an O.Fr. borrowing from Arabic tassah, from Pers. tasht "cup, saucer" (cf. It. tazza, Sp. taza "cup").

demiurge --- 1678, from Latinized form of Gk. demiourgos, lit. "public or skilled worker" (from demos "common people" + ergos "work"). The title of a magistrate in some Gk. city-states and the Achæan League; taken in Platonic philosophy as a name for the maker of the world. In the Gnostic system, "conceived as a being subordinate to the Supreme Being, and sometimes as the author of evil" [OED].

demo --- short for demonstration (tape, disc, etc.). Music recording given out for promotional purposes, 1963. The word was earlier used to mean public political demonstrations (1936).

demob (v.) --- 1920, short for demobilize (1882), from de- + mobilize. Originally in reference to World War I troops returning to civilian life.

democracy --- 1574, from M.Fr. democratie, from M.L. democratia (13c.), from Gk. demokratia, from demos "common people," originally "district" (see demotic), + kratos "rule, strength" (see -cracy). Democratic for one of the two major U.S. political parties is 1829, though members of the Democratic-Republican (formerly Anti-Federal) party had been called Democrats since 1798; though colloquial abbrev. Demo dates to 1793.

demography --- 1880, from Gk. demos "people" (see demotic) + Eng. -graphy "the study of."

demolish --- 1570, from M.Fr. demoliss-, stem of demolir "to destroy, tear down" (1383), from L. demoliri "tear down," from de- "down" + moliri "build, construct," from moles (gen. molis) "massive structure." Demolition is from 1549; demolition derby is 1956, Amer.Eng., defined by OED as "a contest in which old cars are battered into one another, the last one running being declared the winner."

demon --- 1387, from L. dæmon "spirit," from Gk. daimon (gen. daimonos) "lesser god, guiding spirit, tutelary deity," (sometimes including souls of the dead), used (with daimonion) in Christian Gk. translations and Vulgate for "god of the heathen" and "unclean spirit." Jewish authors earlier had employed the Gk. word in this sense, using it to render shedim "lords, idols" in the Septuagint, and Matt. viii.31 has daimones, translated as deofol in O.E., feend or deuil in M.E. The original mythological sense is sometimes written dæmon for purposes of distinction. The Demon of Socrates (1387) was a daimonion, a "divine principle or inward oracle." His accusers, and later the Church Fathers, however, represented this otherwise. The Demon Star (1895) is Beta Persei (in Ar. Algol "the Demon") so called because it visibly varies in brightness every three days. Fem. form demoness first attested 1638. Demonic is from 1662; demonize is from 1821.

demonstration --- c.1374, from L. demonstrationem, from demonstrare, from de- "entirely" + monstrare "to point out, show," from monstrum "divine omen, wonder." Meaning "public show of feeling," usually with a mass meeting and a procession, is from 1839. Demonstrative, of persons, in the sense of "characterized by outward expression of feelings" is from 1819.

demoralize --- c.1793, "to corrupt the morals of," from Fr. demoraliser, from de- "remove" + moral (adj.) (see moral). Said to be a coinage of the Fr. Revolution. Sense of "lower the morale of" (especially of armies) is first recorded 1848.

demote --- 1893 Amer.Eng. coinage from de- + (pro)mote. The original reference describes it as "used generally in that section of the country" (Iowa, U.S.A.), which implies an earlier date. First record of demotion is from 1901.

demotic --- 1822, from Gk. demotikos "of or for the common people," from demos "common people," originally "district," from PIE *da-mo- "division," from base *da- "to divide" (see tide). In contrast to hieratic. Originally of the simpler of two forms of ancient Egyptian writing; broader sense is from 1831; used of Greek since 1927.

demur (v.) --- c.1225, "to linger, tarry," from O.Fr. demorer "delay, retard," from L. demorari, from de- + morari "to delay," from mora "a pause, delay." Main modern sense of "raise objections" is first attested 1639.

demure (adj.) --- 1377, from O.Fr. meur "discreet," from L. maturus "mature." The de- in this word is of uncertain meaning.

den --- O.E. denn "wild animal's lair," from P.Gmc. *danjan. Sense of "small room" is 1771, originally colloquial.

dendrite --- 1727, from Gk. dendrites "of or pertaining to a tree," from dendron "tree."

dendrochronology --- dating by tree rings, 1928, from dendro- (see dendrite) + chronology.

Deneb --- 1867, bright star in the tail of the constellation Cygnus the Swan, from Arabic Al Dhanab al Dajajah "the Hen's Tail."

dengue --- 1828, from W. Indian Sp. dengue, from an African source, perhaps Swahili dinga "seizure, cramp," form influenced by Sp. dengue "prudery" (perhaps because sufferers walk stiffly and erect due to painful joints). The disease is African, introduced to the West Indies 1827.

denial --- 1528, see deny. Meaning "unconscious suppression of painful or embarrassing feelings" first attested 1914 in A.A. Brill's translation of Freud's "Psychopathology of Everyday Life"; popularized 1980s in phrase in denial.

denigrate --- 1526, from L. denigratus, pp. of denigrare "to blacken, defame," from de- "completely" + nigr-, stem of niger "black," of unknown origin. "Apparently disused in 18th c. and revived in 19th c." [OED].

denim --- 1695, from Fr. serge de Nîmes "serge from Nîmes," town in southern France. Application to "coarse cotton cloth" is first recorded 1850 in Amer.Eng.

denizen --- 1419, from Anglo-Fr. deinzein, from deinz "within, inside," from L.L. deintus, from de- "from" + intus "within."

denomination --- 1398, "a naming," from L. denominationem (nom. denominatio) "a calling by anything other than the proper name, metonymy," from denominare "to name," from de- "completely" + nominare "to name." Monetary sense is 1660; meaning "religious sect" is 1716.

denote --- 1592, from M.Fr. denoter, from L. denotare "denote, mark out," from de- "completely" + notare "to mark."

denouement --- 1752, from Fr. dénouement "an untying" (of plot), from dénouer "untie," from O.Fr. desnouer, from des- "un-, out" (from L. dis-) + nouer "to tie, knot" (from L. nodus "a knot").

denounce --- c.1300, from O.Fr. denoncier, from L. denuntiare, from de- "down" + nuntiare "proclaim, announce," from nuntius "messenger" (see nuncio).

dense --- 1599, from L. densus "thick, crowded." Sense of "stupid" is first recorded 1822. Density is from 1603.

dent --- c.1325, "a strike or blow," dialectal variant of M.E. dint (q.v.); sense of "indentation" first recorded 1565, apparently infl. by indent.

dental --- 1594, from M.Fr. dental "of teeth," from L. dens (gen. dentis) "tooth," from PIE base *dont-, *dent- (see tooth).

dentist --- 1759, from Fr. dentiste, from L. dens (gen. dentis) "tooth," from PIE base *dont-, *dent- (see tooth). "Dentist figures it now in our newspapers, and may do well enough for a French puffer, but we fancy Rutter is content with being called a tooth-drawer" ["Edinburgh Chronicle," Sept. 15, 1759]. Tooth-drawer is attested from 1393.

denture --- 1874, from Fr. denture "set of teeth," from L. dens (gen. dentis) "tooth," from PIE base *dont-, *dent- (see tooth).

denude --- 1513, from M.Fr. denuder, from L. denudare, from de- "away" + nudare "to strip," from nudus "bare."

denunciation --- 1548; see denounce.

Denver --- city in Colo., founded 1858 as Auraria ("golden"), renamed 1859 for Gen. James W. Denver (1817-92), governor of the territory. The family name is from the place of that name in Norfolk, lit. "ford or passage used by the Danes," from O.E. Dena (gen. pl.) + fær. The Denver boot or shoe as the name for a wheel clamp for illegally parked vehicles, supposedly was invented 1953 by Frank Marugg, pattern-maker and violinist with the Denver (U.S.A.) Symphony Orchestra. He was a friend of politicians and police department officials, and the city sheriff's department came to him for help in making a device to immobilize vehicles whose owners didn’t pay parking tickets.

deny --- c.1300, from O.Fr. denier, from L. denegare, from de- "away" + negare "refuse, say 'no,' " from Old L. nec "not," from Italic base *nek- "not," from PIE base *ne- "no, not" (see un-).

Deo volente --- 1767, L., lit. "God willing."

deodand --- 1523, from Anglo-Fr. deodande (1292), from M.L. deodandum, from Deo dandum "a thing to be given to God." In Eng. law, "a personal chattel which, having been the immediate cause of the death of a person, was forfeited to the Crown to be applied to pious uses." Abolished 1846.

deodorant --- 1869 (deodorize is 1858), formed in Eng. as if from L. odorem "smell." An earlier version, a perfumed powder, was called empasm (1657), from Gk. *empasma "to sprinkle on."

deoxyribonucleic acid --- 1931

depart --- c.1225, from O.Fr. departir, from L.L. departire "divide" (transitive), from de- "from" + partire "to part, divide," from pars (gen. partis) "a part." As a euphemism for "to die" (to depart this life) it is attested from 1501. Fr. department meant "group of people" (as well as "departure"), from which Eng. borrowed sense of "separate division" (c.1735) found in department store (1847). Transitive in Eng. lingers in some senses; the wedding service was till death us depart until 1662.

depend --- 1413, "to be attached to as a condition or cause," fig. use, from M.Fr. dependre "to hang from, hang down," from L. dependere, from de- "from, down" + pendere "to hang, be suspended" (see pendant). Dependence was spelled -ance from time of borrowing from Fr. c.1400 until respelling c.1800 by influence of Latin; dependant (1523) usually retains the Fr. form. Dependable is from 1735.

depict --- c.1430, from L. depictus, pp. of depigere, from de- "down" + pingere "to paint" (see paint).

depilatory --- 1601, from Fr. depilatorie (adj.), from L. depilatus "having one's hair plucked," from de- "completely" + pilatus, pp. of pilare "deprive of hair," from pilus "hair."

depletion --- 1656, from L.L. depletionem (nom. depletio) "blood-letting," from L. deplere "to empty," lit. "to un-fill," from de- "off, away" + plere "to fill" (see plenary). Deplete is an 1807 back-formation.

deplore --- 1559, from L. deplorare "deplore, bewail," from de- "entirely" + plorare "weep, cry out."

deploy --- 1786 as a military word, from Fr. déployer "unroll, unfold," from O.Fr. desployer "unfold," from L. displicare "unfold, scatter," from dis- + plicare "to fold" see ply (v.)).

depopulate --- 1545, from de- + populate.

deport --- 1474, "behavior, bearing," from M.Fr. deporter "behave," from de- "thoroughly, formally" + porter "to carry, bear oneself;" original sense preserved in deportment (1601). Meaning "banish" is first recorded 1641, from Fr. déporter, from L. deportare "carry off, transport, banish;" associated by folk etymology with portus "harbor." Deportee first attested 1895.

depose --- c.1300, from O.Fr. deposer, from de- "down" + poser "put, place" (see pose). Deposition (1494 in the legal sense) belongs to deposit, but that word and this one have become totally confused.

deposit --- 1624, from L. depositus, pp. of deponere "lay aside, put down, deposit," from de- "away" + ponere "to put" (see position). Geological sense is from 1781; monetary sense is from 1737.

depot --- 1795, "warehouse," from Fr. dépôt "a deposit, place of deposit," from O.Fr. depost "a deposit or pledge," from L. depositum "a deposit," neut. pp. of deponere "lay aside" (see deposit). Military sense is from 1798; meaning "railway station" is first recorded 1842, Amer.Eng.

deprave --- 1362, from O.Fr. depraver, from L. depravare "corrupt," from de- "completely" + pravus "crooked."

deprecation --- 1490 (deprecative), from M.Fr. deprécation, from L. deprecationem, from deprecari "plead in excuse, avert by prayer," from de- "away" + precari "pray." Sense of "show disapproval" is first attested 1612.

depreciate --- 1646, from L. depretiatus, pp. of depretiare, from de- "down" + pretium "price" (see price).

depredation --- 1483, from L.L. deprædationem (nom. deprædatio), from L. deprædari "to pillage," from de- "thoroughly" + prædari "to plunder," lit. "to make prey of," from præda "prey."

depress --- c.1325, from O.Fr. depresser, from L.L. depressare, freq. of L. deprimere "press down," from de- "down" + premere "to press" (see press (v.1)). Economic sense of depression is 1793, given a specific application in 1934 to the one that began worldwide in 1929; sense of "state of dejection" is c.1425; adopted 1905 as a clinical term in psychology. Depressant "sedative" is first attested 1876.

deprive --- c.1325, from M.L. deprivare, from L. de- "entirely" + privare "release from." Replaced O.E. bedælan.

deprogram --- release from cult brainwashing, 1973, from de- + program (v.).

depth --- 1382, apparently formed 14c. on model of length, breadth, from O.E. deop "deep," replacing older deopnes. Corresponds to O.N. dypð, Goth. diupiþa.

deputy --- 1406, "one given the full power of an officer without holding the office," from Anglo-Fr. depute, n. use of pp. of M.Fr. deputer "appoint, assign," from L.L. deputare "to destine, allot," from L. deputare "consider as," from de- "away" + putare "to think, count, consider," lit. "to cut."

deracinate --- 1599, "to pluck up by the roots," from Fr. déraciner, from O.Fr. desraciner, from des- + racine "root."

derail --- 1850, in both trans. and intrans. senses, from Fr. dérailler, first in general use in U.S. See rail.

derange --- 1776, from Fr. déranger, from O.Fr. desrengier "disarrange," from des- "do the opposite of" + reng "line, row" (see rank). Mental sense first recorded 1825.

derby --- type of hat, manufactured in U.S. 1850, name appears 1870, from annual Derby horse race in England, where this type of hat was worn. Race was begun 1780 by the 12th Earl of Derby; Parliament always adjourned for it, and the name was used for any major horse race after 1875. Derby the English shire is O.E. Deorby "deer village," from deor "deer" + by "habitation, homestead," from a Scand. source (see bylaw).

deregulation --- 1963, from de- + regulation.

derelict (adj.) --- 1649, from L. derelictus, pp. of dereliquere "abandon," from de- "entirely" + relinquere "leave behind" (see relinquish). Originally especially of vessels abandoned at sea or stranded on shore. Dereliction "failure in duty" is from 1830.

derision --- c.1400, from O.Fr. derision (13c.), from L. derisionem, noun of action from deridere "ridicule," from de- "down" + ridere "to laugh." Deride is 1530, from M.Fr. derider.

derive --- c.1385, from O.Fr. deriver, from L. derivare "to lead or draw off (a stream of water) from its source," from phrase de rivo (de "from" + rivus "stream"). Etymological sense is c.1560. Derivative is from 1530.

dermatologist --- 1861, from Gk. derma (gen. dermatos) "skin, hide, leather." Dermabrasion first attested 1954.

derogatory --- 1502, from L. derogatorius, from derogare "detract from," also "repeal partly," from de- "away" + rogare "ask, question, propose" (see rogation).

derrick --- c.1600, originally "hangman," then "a gallows," then "hoist, crane" (1727), from surname of a hangman at Tyburn gallows, London, c.1606-1608, often referred to in contemporary theater. The name represents a late borrowing from the Low Countries (cf. Du. Diederik) of O.H.G. Theodric.

derriere --- 1774, from Fr. derrière "back part, rear," originally an adv., "behind," from L.L. deretro, from L. de "from" + retro "back."

derring-do --- originally (c.1374) dorrying don, lit. "daring to do," from durring "daring," prp. of M.E. durren "to dare" (see dare) + don, inf. of "to do." Misspelled derrynge do 1500s and mistaken for a noun by Spenser, who took it to mean "manhood and chevalrie;" picked up from him and passed on to Romantic poets as a pseudo-archaism by Sir Walter Scott.

derringer --- 1850, for Henry Deringer (1786-1868), U.S. gunsmith who invented it in the 1840s; prevailing misspelled form is how his name appeared on the many counterfeits and imitations. "A small pistol with a large bore, very effective at short range" [OED].

dervish --- 1585, from Turk. dervish, from Pers. darvesh, darvish "beggar, poor," hence "religious mendicant;" equivalent of Arabic faqir (cf. fakir). The "whirling dervishes" are just one order among many.

descant --- c.1380, from Anglo-Fr. deschaunt, from M.L. discantus "refrain, part-song," from L. dis- "asunder, apart" + cantus "song." Spelling was partly Latinized 16c. Originally "counterpoint;" sense of "talk at length" is first attested 1649.

descend --- c.1300, from O.Fr. descendre, from L. descendere, from de- "down" + scandere "to climb," from PIE base *skand- "jump." Sense of "originate from" is c.1375. Descent is attested from c.1330; descendant "offspring" is from 1600.

deschooling --- 1970, coined by Austrian-born U.S. anarchist philosopher Ivan Illich (b.1926) for "the transfer of education to non-institutional systems," from de- + schooling.

description --- 1340, from L. descriptionem, from stem of describere "write down, transcribe, copy, sketch," from de- "down" + scribere "write" (see script). Describe (1513) is a reconstruction from L., replacing earlier descrive (c.1225). Descriptive is first recorded 1751.

descry --- c.1300, probably from O.Fr. descrier "publish," from L. describere (see describe).

desecrate --- 1674, formed from de- "do the opposite of" + (con)secrate. O.Fr. had dessacrer "to profane," and there is a similar formation in It.; but L. desecrare meant "to make holy," with de- in this case having a completive sense.

desegregation --- 1952, Amer.Eng., from de- "do the opposite of" + segregation "apartheid" (see segregate).

desensitize --- 1904, from de- "do the opposite of" + sensitize. Originally of photography development; psychological sense is first recorded 1935.

desert (n.1) --- wasteland, c.1225, from O.Fr. desert, from L.L. desertum, lit. "thing abandoned" (used in Vulgate to translate "wilderness"), n. use of neut. pp. of L. deserere "forsake" (see desert (v.)). Sense of "waterless, treeless region" was in M.E. and gradually became the main meaning. Commonly spelled desart in 18c., which is not etymological but at least avoids confusion with the other two senses of the word. Desertification was coined 1973 (desertization was used in 1968).

desert (n.2) --- suitable reward or punishment (now usually plural and just), 1297, from O.Fr. deserte, pp. of deservir "be worthy to have," from L. deservire "serve well" (see deserve).

desert (v.) --- to leave, c.1380, from O.Fr. deserter "leave," lit. "undo or sever connection," from L.L. desertare, freq. of L. deserere "to abandon," from de- "undo" + serere "join" (see series). Military sense is first recorded 1647.