Online Etymology Dictionary

down (adv.): late Old English shortened form of Old English ofdune "downwards," from dune "from the hill," dative of dun "hill" (see down (n.2)). A sense development peculiar to English.

Used as a preposition since c. 1500. Sense of "depressed mentally" is attested from c. 1600. Slang sense of "aware, wide awake" is attested from 1812. Computer crash sense is from 1965. As a preposition from late 14c.; as an adjective from 1560s. Down-and-out is from 1889, American English, from situation of a beaten prizefighter. Down home (adj.) is 1931, American English; down the hatch as a toast is from 1931; down to the wire is 1901, from horse-racing. Down time is from 1952. Down under "Australia and New Zealand" attested from 1886; Down East "Maine" is from 1825; Down South "in the Southern states of the U.S." is attested by 1834.
down (n.1): "soft feathers," late 14c., from Old Norse dunn, perhaps ultimately from PIE root *dheu- (1) "to fly about (like dust), to rise in a cloud."
down (n.2): Old English dun "down, moor; height, hill, mountain," from Proto-Germanic *dunaz- (source also of Middle Dutch dunen "sandy hill," Dutch duin), "probably a pre-insular loan-word from Celtic" [Cambridge Dictionary of English Place-Names], in other words, borrowed at a very early period, before the Anglo-Saxon migration, from PIE root *dheue- "to close, finish, come full circle." Meaning "elevated rolling grassland" is from c. 1300.

The non-English Germanic words tend to mean "dune, sand bank" (see dune), while the Celtic cognates tend to mean "hill, citadel" (compare Old Irish dun "hill, hill fort;" Welsh din "fortress, hill fort;" and second element in place names London, Verdun, etc.). German Düne, French dune, Italian, Spanish duna are said to be loan-words from Dutch.
down (v.): 1560s, from down (adv.). Meaning "swallow hastily" is by 1860; football sense of "bring down (an opposing player) by tackling" is attested by 1887. Related: Downed; downing.
Down's Syndrome: 1961, from J.L.H. Down (1828-1896), English physician; chosen as a less racist name for the condition than earlier mongolism.
down-hearted (adj.): also downhearted, 1774 (downheartedly is attested from 1650s), a figurative image from down (adv.) + hearted.
down-to-earth (adj.): also down to earth, as an adjectival phrase, attested from 1932.
downbeat: 1876 (n.), in reference to downward stroke of a conductor's baton; 1952 (adj.) in figurative sense of "pessimistic," but that is probably via associations of the word down (adv.), because the beat itself is no more pessimistic than the upbeat is optimistic.
downcast (adj.): c. 1600, from past participle of obsolete verb downcast (c. 1300), from down (adv.) + cast (v.). Literal at first; figurative sense is 1630s.
downer (n.): 1966 in sense of "barbiturate;" 1970 in sense of "depressing person;" agent noun from down (v.).
downfall (n.): "ruin, fall from high condition," c. 1300, from down (adv.) + fall (v.).
downgrade (v.): 1930, from down (adv.) + grade (v.). Related: Downgraded; downgrading. As a noun, "a downward slope," from 1858.
downhill: 1590s (n.); 1650s (adv.), 1727 (adj.), from down (adv.) + hill (n.). Meaning "downhill skiing race" is from 1960.
Downing Street: short street in London, named for British diplomat Sir George Downing (c. 1624-1684). It contains the residence of the prime minister (at Number 10), hence its metonymic use for "the British government," attested from 1781.
download: 1977 (n.), 1980 (v.), from down (adv.) + load (v.). Related: Downloaded; downloading.
downplay (v.): "de-emphasize," 1968, from down (adv.) + play (v.). Related: Downplayed; downplaying.
downpour (n.): 1811, from verbal phrase, down (adv.) + pour (v.).
downright (adv.): c. 1200, "straight down," from down (adv.) + right (adj.1). Meaning "thoroughly" attested from c. 1300. Old English had dunrihte "downwards," and inverted form right-down is attested 17c.
downscale (v.): 1945, American English, from down (adv.) + scale (v.). From 1966 as an adjective.
downside (n.): 1680s, "underside," from down (adv.) + side. Meaning "drawback, negative aspect" is attested by 1995.
downsize (v.): 1986 in reference to companies shedding jobs; earlier (1975) in reference to U.S. automakers building smaller cars and trucks (supposedly a coinage at General Motors), from down (adv.) + size (v.). Related: Downsized; downsizing.
downspout (n.): 1896, from down (adv.) + spout (n.).
downstairs (adv., adj.): 1590s, from down (adv.) + stairs (see stair).
downstream (adv., adj.): 1706, from down (prep.) + stream (n.).
downtime (n.): 1952, from down (adv.) + time (n.).
downtown (n.): 1835, from down (adv.) + town. The notion is of suburbs built on heights around a city.
downtrodden (adj.): 1560s, "stepped on," from down (adv.) + trodden. Figurative use, "oppressed," is from 1590s.
downturn (n.): 1926 in the economic sense, from down (adv.) + turn (n.).
downward (adv.): c. 1200, from down (adv.) + -ward. Old English had aduneweard in this sense. Downwards, with adverbial genitive, had a parallel in Old English ofduneweardes.
downy (adj.): 1570s, from down (n.1) + -y (2).
dowry (n.): early 14c., from Anglo-French dowarie, Old French doaire (late 13c.) "dower, dowry, gift," from Medieval Latin dotarium, from Latin dotare "to endow, portion," from dos (genitive dotis) "marriage portion," from PIE *do-ti (source also of Sanskrit dadati, Greek didonai, Old Church Slavonic dati, Lithuanian duoti, Armenian tam, all meaning "to give"), from root *do- "to give" (see date (n.1)).
dowse (v.): 1690s, a south England dialect word, of uncertain origin, said to have been introduced to Devon by German miners in Elizabethan times. Related: Dowsed; dowsing.
doxology (n.): "hymn of praise," 1640s, from Medieval Latin doxologia, from Ecclesiastical Greek doxologia "praise, glory," from doxologos "praising, glorifying," from doxa "glory, praise" (from dokein "to seem good;" see decent) + logos "a speaking" (see lecture (n.)).
doxy (n.): "rogue's girlfriend," 1520s, slang, of unknown origin (see dell (n.2)). Liberman says it is probably from Low German dokke "doll," "with the deterioration of meaning from 'sweetheart' and 'wench' to 'whore.'"
doyen: early 15c., from Middle French doyen "commander of ten," from Old French deien (see dean).
doyenne: 1905, from fem. of French doyen (see doyen). As a type of pear, from 1731.
doze (v.): 1640s, probably from a Scandinavian source (compare Old Norse dusa "to doze," Danish døse "to make dull," Swedish dialectal dusa "to sleep"); related to Old English dysig "foolish" (see dizzy). May have existed in dialect earlier than attested date. Related: Dozed; dozing. As a noun, from 1731.
dozen (n.): c. 1300, from Old French dozaine "a dozen," from doze (12c.) "twelve," from Latin duodecim "twelve," from duo "two" + decem "ten" (see ten).

The Old French fem. suffix -aine is characteristically added to cardinals to form collectives in a precise sense ("exactly 12," not "about 12"). The dozens "invective contest" (1928) originated in slave culture, the custom probably African, the word probably from bulldoze (q.v.) in its original sense of "a whipping, a thrashing."
dozy (adj.): "drowsy," 1690s, from doze + -y (2).
Dr. Pepper (n.): soft drink, patented 1906 by the Dr. Pepper Co., Dallas, Texas; named for U.S. physician Dr. Charles Pepper.
drab (n.): 1680s, "color of natural, undyed cloth," from Middle French drap "cloth, piece of cloth" (see drape (v.)). Figurative sense is c. 1880. Apparently not related to earlier word drab, meaning "a dirty, untidy woman" (1510s), "a prostitute" (1520s), which might be related to Irish drabog, Gaelic drabag "dirty woman," or perhaps it is connected with Low German drabbe "dirt;" compare drabble (Middle English drabelen) "to soil (something); trail in the mud or on the ground" (c. 1400). Ultimately perhaps from PIE *dher- (1) "to make muddy." Meaning "small, petty debt" (the sense in dribs and drabs) is 1828, of uncertain connection to the other senses.
drachma (n.): 1570s, from Latinized form of Greek drakhme, an Attic coin and weight, probably originally "a handful" (see dram). Earlier in English as dragme (late 14c.), from Old French dragme, from Medieval Latin dragma.
Draco (n.): northern constellation representing a dragon, from Latin draco "dragon" (see dragon). Identified as such since ancient times.
draconian (adj.): 1876 (earlier Draconic, implied from 1640s), from Draco, Greek statesman who laid down a code of laws for Athens 621 B.C.E. that mandated death as punishment for minor crimes. His name seems to mean literally "sharp-sighted" (see dragon).
Dracula (n.): the vampire from in Bram Stoker's novel (1897). It was a surname of Prince Vlad II of Wallachia (d.1476), and means in Romanian "son of Dracul," literally "the dragon," from the name and emblem taken by Vlad's father, also named Vlad, c. 1431 when he joined the Order of the Dragon, founded 1418 by Sigismund the Glorious of Hungary to defend the Christian religion from the Turks and crush heretics and schismatics.
draft (n.): c. 1500, spelling variant of draught (q.v.) to reflect change in pronunciation. Among the senses that have gone with this form of the word in American English, the meaning "rough copy of a writing" (something "drawn") is attested from 14c.; that of "preliminary sketch from which a final copy is made" is from 1520s; that of "flow of a current of air" is from c. 1770. Of beer from the 1830s, in reference to the method of "drawing" it from the cask. Sense in bank draft is from 1745. The meaning "a drawing off a group for special duty" is from 1703, in U.S. especially of military service; the verb in this sense first recorded 1714. Related: Drafted; drafting.
draftee (n.): 1864, in a military context, American English, from draft + -ee.
draftsman (n.): 1660s, variant of draughtsman; also see draft.
drafty (adj.): 1580s, from draft "current of air" + -y (2). Related: Draftiness.
drag (v.): mid-15c., from Old Norse draga, or a dialectal variant of Old English dragan "to draw," both from Proto-Germanic *dragan "to draw, pull," from PIE root *dhragh- "to draw, drag on the ground" (source also of Sanskrit dhrajati "pulls, slides in," Russian drogi "wagon;" but not considered to be directly the source of Latin trahere).

Meaning "to take a puff" (of a cigarette, etc.) is from 1914. Related: Dragged; dragging. Drag-out "violent fight" is from c. 1859. To drag (one's) feet (1946, in figurative sense) supposedly is from logging, from a lazy way to use a two-man saw.