doctrine (n.) Look up doctrine at Dictionary.com
late 14c., from Old French doctrine (12c.) "teaching, doctrine," and directly from Latin doctrina "teaching, body of teachings, learning," from doctor "teacher" (see doctor (n.)).
document (n.) Look up document at Dictionary.com
early 15c., "teaching, instruction," from Old French document (13c.) "lesson, written evidence," from Latin documentum "example, proof, lesson," in Medieval Latin "official written instrument," from docere "to show, teach" (see doctor (n.)). Meaning "something written that provides proof or evidence" is from early 18c. Related: Documents.
document (v.) Look up document at Dictionary.com
1640s, "to teach;" see document (n.). Meaning "to support by documentary evidence" is from 1711. Related: Documented; documenting.
documentary (adj.) Look up documentary at Dictionary.com
c.1810, "pertaining to documents," from document + -ary. Meaning "factual, meant to provide a record of something" is from 1926, from French film documentarie (1924). The noun (short for documentary film) is attested from 1935. Docudrama is a 1961 coinage.
documentation (n.) Look up documentation at Dictionary.com
1754, "admonition," from Medieval Latin documentationem (nominative documentio) "admonition" (see document). Meaning "furnishing with documents or papers" is from 1884, probably from document. Meaning "collection of informational papers" is from 1927.
dodder (v.) Look up dodder at Dictionary.com
1610s, perhaps from Middle English daderen "to quake, tremble" (late 15c.), apparently frequentative of dialectal dade, on a form similar to totter, patter. Related: Doddered; doddering.
dodecahedron (n.) Look up dodecahedron at Dictionary.com
1560s, from Greek dodeka "twelve" (short for duodeka, from duo "two" + deka "ten;" compare dozen) + hedra "seat, base, chair, face of a geometric solid," from PIE root *sed- (1) "to sit" (see sedentary).
dodge (n.) Look up dodge at Dictionary.com
"person's way of making a living," 1842, slang, from dodge (v.).
dodge (v.) Look up dodge at Dictionary.com
"to move to and fro" (especially in an effort to avoid something), 1560s, origin and sense evolution obscure, perhaps akin to Scottish dodd "to jog." Common from early 18c. in figurative sense of "to swindle, to play shifting tricks." Related: Dodged; dodging.
dodger (n.) Look up dodger at Dictionary.com
1560s, "one who dodges," in the literal or figurative (especially underworld) senses of dodge. The U.S. word meaning "corn cake" is recorded from 1831, perhaps a different word (compare Northern English dialectal dodge "lump, large piece," 1560s).
Dodgers Look up Dodgers at Dictionary.com
U.S. baseball club, originally based in Brooklyn, N.Y., so called from 1900, from trolley dodgers, Manhattanites' nickname for Brooklyn residents, in reference to the streetcar lines that criss-crossed the borough.
dodgy (adj.) Look up dodgy at Dictionary.com
1861, from dodge + -y (2). Related: Dodginess.
dodo (n.) Look up dodo at Dictionary.com
1620s, from Portuguese doudo "fool, simpleton," an insult applied by Portuguese sailors to the awkward bird (Didus ineptus) they found on Mauritius island. The last record of a living one is from 1681. Applied in English to stupid persons since 1886.
doe (n.) Look up doe at Dictionary.com
Old English da "a female deer," of unknown origin, perhaps a Celtic loan-word (compare Cornish da "fallow deer," Old Irish dam "ox," Welsh dafad "sheep").
doer (n.) Look up doer at Dictionary.com
c.1300, agent noun from do.
does Look up does at Dictionary.com
third person singular present of do (v.), originally a Northumbrian variant in Old English that displaced doth, doeth 16c.-17c.
doesn't Look up doesn't at Dictionary.com
1690s, contraction of does not.
doff (v.) Look up doff at Dictionary.com
mid-14c., contraction of do off, preserving the original sense of do as "put." At the time of Johnson's Dictionary [1755] the word was "obsolete, and rarely used except by rustics," but it was saved from extinction (along with don) by Sir Walter Scott. Related: Doffed; doffing.
dog (n.) Look up dog at Dictionary.com
Old English docga, a late, rare word used of a powerful breed of canine. It forced out Old English hund (the general Germanic and Indo-European word; see canine) by 16c. and subsequently was picked up in many continental languages (French dogue (16c.), Danish dogge), but the origin remains one of the great mysteries of English etymology.

Many expressions -- a dog's life (c.1600), go to the dogs (1610s), etc. -- reflect earlier hard use of the animals as hunting accessories, not pampered pets. In ancient times, "the dog" was the worst throw in dice (attested in Greek, Latin, and Sanskrit, where the word for "the lucky player" was literally "the dog-killer"), which plausibly explains the Greek word for "danger," kindynas, which appears to be "play the dog."

Slang meaning "ugly woman" is from 1930s; that of "sexually aggressive man" is from 1950s. Adjectival phrase dog-eat-dog attested by 1850s. Dog tag is from 1918. To dog-ear a book is from 1650s; dog-eared in extended sense of "worn, unkempt" is from 1894.
Notwithstanding, as a dog hath a day, so may I perchance have time to declare it in deeds. [Princess Elizabeth, 1550]
Phrase put on the dog "get dressed up" (1934) may look back to the stiff stand-up shirt collars that in the 1890s were the height of male fashion (and were known as dog-collars at least from 1883), with reference to collars worn by dogs. The common Spanish word for "dog," perro, also is a mystery word of unknown origin, perhaps from Iberian. A group of Slavic "dog" words (Old Church Slavonic pisu, Polish pies, Serbo-Croatian pas) likewise are of unknown origin.
dog (v.) Look up dog at Dictionary.com
"to track like a dog," 1510s, see dog (n.). Related: Dogged; dogging.
dog days (n.) Look up dog days at Dictionary.com
1530s, from Latin dies caniculares, from Greek; so called because they occur around the time of the heliacal rising of Sirius, the Dog Star (kyon seirios). Noted as the hottest and most unwholesome time of the year; usually July 3 to Aug. 11, but variously calculated, depending on latitude and on whether the greater Dog-star (Sirius) or the lesser one (Procyon) is reckoned.

The heliacal rising of Sirius has shifted down the calendar with the precession of the equinoxes; in ancient Egypt c.3000 B.C.E. it coincided with the summer solstice, which also was the new year and the beginning of the inundation of the Nile. The "dog" association apparently began here (the star's hieroglyph was a dog), but the reasons for it are obscure.
dog leg (n.) Look up dog leg at Dictionary.com
"something bent like a dog's hind leg," 1703. Originally of a type of staircase.
doge (n.) Look up doge at Dictionary.com
"chief magistrate of Venice or Genoa," 1540s, from Venetian dialect doge, from Latin ducem, accusative of dux "leader" (see duke (n.)).
dogfight (n.) Look up dogfight at Dictionary.com
"aerial combat," World War I air forces slang, from earlier meaning "riotous brawl" (1880s); from dog (n.) + fight (n.). The literal sense of "a fight among or between dogs" is from 1650s.
dogfish (n.) Look up dogfish at Dictionary.com
a name for various types of small shark, late 15c., dokefyche, from dog (n.) + fish (n.). Said to be so called because they hunt in packs. This was the image of sharks in classical antiquity as well.
But in the Mediterranean, among the Greeks and Romans of antiquity, closer contact with sharks had left an impression of vicious dogs of the sea. Thus, Pliny's canis marinus. The metaphor of the dog spread to the North to dominate the European image of the shark, from the Italian pescecane and French chien de mer to the German Meerhund and Hundfisch and English sea dog and dogfish. [Tom Jones, "The Xoc, the Sharke and the Sea Dogs," in "Fifth Palenque Round Table, 1983," edited by Virginia M. Field, 1985.]
dogged (adj.) Look up dogged at Dictionary.com
"having the qualities of a dog" (mostly in a negative sense), c.1300, from dog (n.). Meaning "persistent" is from 1779. Hence doggedly (late 14c.), "cruelly, maliciously;" later "with a dog's persistence" (1773). Related: Doggedness.
dogger (n.) Look up dogger at Dictionary.com
"two-masted fishing boat," used in North Sea fishery, mid-14c., of unknown origin. It likely is the source of the name Dogger Bank (1660s) for the great banks of shoals in the North Sea.
doggerel Look up doggerel at Dictionary.com
late 14c. (adj.); 1630s (n.), "Any rhyming verse in which the meter is forced into metronomic regularity by the stressing of normally unstressed syllables and in which rhyme is forced or banal" [Miller Williams, "Patterns of Poetry"]. probably from dog (n.) + pejorative suffix -rel and applied to bad poetry perhaps with a suggestion of puppyish clumsiness, or being fit only for dogs. Attested as a surname from mid-13c., but the sense is not evident.
doggone (adj.) Look up doggone at Dictionary.com
1851, American English, a "fantastic perversion of god-damned" [Weekley]. But Mencken favors the theory that it is "a blend form of dog on it; in fact it is still often used with it following. It is thus a brother to the old English phrase, 'a pox upon it,' but is considerably more decorous."
doggy (n.) Look up doggy at Dictionary.com
also doggie, 1825, from dog (n.) + -y (3). Doggy-bag attested from 1965. As an adj. doggy is attested from late 14c., from -y (2). The word has been used in various formations since at least late 19c. to describe the sex act when one partner is on all fours.
doghouse (n.) Look up doghouse at Dictionary.com
1610s, from dog (n.) + house (n.). Originally a kennel; the backyard type, for a single animal, is late 19c. Figurative sense of "disgrace" is from 1932.
dogie (n.) Look up dogie at Dictionary.com
"motherless calf in a herd," 1887, cowboy slang, of uncertain origin.
dogma (n.) Look up dogma at Dictionary.com
c.1600 (in plural dogmata), from Latin dogma "philosophical tenet," from Greek dogma (genitive dogmatos) "opinion, tenet," literally "that which one thinks is true," from dokein "to seem good, think" (see decent). Treated in 17c.-18c. as a Greek word in English.
dogmatic (adj.) Look up dogmatic at Dictionary.com
1670s, from Late Latin dogmaticus, from Greek dogmatikos "pertaining to doctrines," from dogma (see dogma). Related: Dogmatical (c.1600).
dogmatism (n.) Look up dogmatism at Dictionary.com
c.1600, but not in common use until 19c., from French dogmatisme (16c.), from Medieval Latin dogmatismus, from Latin dogma (see dogma).
dogs (n.) Look up dogs at Dictionary.com
"feet," 1913, from rhyming slang dog's meat.
dogwood (n.) Look up dogwood at Dictionary.com
shrubs and small trees of the genus Cornus, 1610s, earlier dog-tree (1540s); the first element sometimes said to have been perhaps dag -- compare dagger, dag (v.) "to pierce or stab" (1630s, perhaps 15c.) -- the trees have hard, white wood that was used in making skewers; another name for it was skewer-wood. But another guess is that the tree was given the name in reference to its fruit, which was called dogberry from 1550s, and dog had implications of "cheap, inferior" (i.e. "fit for a dog").
doily (n.) Look up doily at Dictionary.com
1714, short for doily-napkin (1711), from doily "thin, woolen fabric;" supposedly from Doiley, surname of a 17c.-early 18c. dry-goods dealer on London's Strand. Doily earlier meant "genteel, affordable woolens" (1670s), evidently from the same source. The surname is d'Ouilly, from one of several places called Ouilly in Normandy.
doing (n.) Look up doing at Dictionary.com
early 13c., verbal noun from do (v.). From c.1600-1800 it also was a euphemism for "copulation."
dojo (n.) Look up dojo at Dictionary.com
"hall in which judo is practiced," 1942, from Japanese.
dol (n.) Look up dol at Dictionary.com
unit of intensity of pain, 1947, from Latin dolor "pain."
Dolby Look up Dolby at Dictionary.com
sound reproduction system, 1966, named for its inventor, U.S. engineer Ray M. Dolby (b.1933).
dolce far niente Look up dolce far niente at Dictionary.com
1814, from Italian, literally "sweet doing nothing." The Latin roots are dulcis "sweet" (see dulcet), facere "to make, do" (see factitious), and nec entem, literally "not a being."
This phrase, frequent enough in English literature, does not seem to occur in any Italian author of note. Howells says that he found it current among Neapolitan lazzaroni, but it is not included in any collection of Italian proverbial sayings. [Walsh]
dolce vita (n.) Look up dolce vita at Dictionary.com
"life of pleasure," 1960, Italian, from title of Fellini's film.
doldrums (n.) Look up doldrums at Dictionary.com
1811, from dulled, past participle of dullen, from Old English dol "foolish, dull," ending perhaps patterned on tantrum.
dole (n.) Look up dole at Dictionary.com
Old English dal "state of being divided; sharing, giving out," shortened from gedal "portion," related to dæl "deal," from Proto-Germanic *dailiz (cognates: Old Frisian and Old Saxon del, Middle Dutch deil, Dutch deel, Old High German teil, German Teil). On the dole is 1920s.
dole (v.) Look up dole at Dictionary.com
"hand out charity," mid-15c., from dole (n.). Doled; doling.
doleful (adj.) Look up doleful at Dictionary.com
late 13c., with -ful, from Middle English dole "grief" (early 13c.), from Old French doel (Modern French deuil), from Late Latin dolus "grief," from Latin dolere "suffer, grieve." Related: Dolefully.
doll (n.) Look up doll at Dictionary.com
1550s, endearing name for a female pet or a mistress; originally a familiar form of fem. proper name Dorothy (q.v.). The -l- for -r- substitution in nicknames is common in English: compare Hal for Harold, Moll for Mary, Sally for Sarah, etc. Attested from 1640s as colloquial for "slattern;" sense of "child's toy baby" is c.1700. Transferred back to living beings 1778 in sense of "pretty, silly woman."
doll (v.) Look up doll at Dictionary.com
1867, "to pet, indulge," from doll (n.). Usually with up. Meaning "to dress up" is from 1906, American English. Related: Dolled; dolling.