Online Etymology Dictionary

coda (n.): "concluding passage in a musical composition," 1753, from Latin cauda "tail of an animal."
coddle (v.): c.1600, "boil gently," probably from caudle "warm drink for invalids" (c.1300), from Anglo-French caudel (c.1300), ultimately from Latin calidium "warm drink, warm wine and water," neuter of calidus "hot," from calere "be warm" (see calorie). Verb meaning "treat tenderly" first recorded 1815 (in Jane Austen's "Emma"). Related: Coddled; coddling.
code (n.): c.1300, "systematic compilation of laws," from Old French code "system of laws, law-book" (13c.), from Latin codex, earlier caudex "book, book of laws," literally "tree trunk," hence, book made up of wooden tablets covered with wax for writing. Meaning "cipher" (the sense in secret code) is from 1808.
code (v.): 1815, from code (n.). Specifically in the computer sense from 1947. Related: Coded; coding.
codec (n.): by 1970, an abbreviation from compressor-decompressor or coder-decoder, on model of modem.
codefendant (n.): also co-defendant, 1640s, from co- + defendant.
codeine (n.): alkaloid present in opium, 1838, from French codéine, coined, with chemical suffix -ine (2), from Greek kodeia "poppy head," related to kooz "prison," literally "hollow place;" kodon "bell, mouth of a trumpet;" koilos "hollow," from PIE root *kel- (see cell). Originally codeina; modern form is from 1881.
codependent (adj.): also co-dependent, by 1905, in various senses, from co- + dependent. Modern psycological sense is attested from c.1983. Related: Codependence, codependency.
codex (n.): "manuscript volume (especially an ancient one)," 1845, from Latin codex (see code (n.)).
codger (n.): 1756, probably a variant of cadger "beggar" (see cadge (v.)), which is of unknown origin.
codicil (n.): early 15c., from Middle French codicille, from Latin codicillus "a short writing, a small writing tablet," dimibnutive of codex (genitive codicis), see code (n.).
codify (v.): c.1800, from code (n.) + -fy. Related: codified; codifying; codification.
codominant (adj.): also co-dominant, 1926, from co- + dominant.
codon (n.): 1962, from code (n.) + -on.
codpiece (n.): mid-15c., "a bagged appendage to the front of the breeches; often conspicuous" [OED], from Old English codd "a bag, pouch, husk," in Middle English, "testicles" (common Germanic, cf. Old Norse koddi "pillow," Dutch kodde "bag") + piece (n.).
codswallop (n.): said to be from 19c. (but first attested 1963), perhaps from wallop, British slang for "beer," and cod in one of its various senses, perhaps "testicles."
coe (n.): "hut built over a mine shaft," 1650s, from some source akin to Dutch kouw, German kaue in the same sense, from West Germanic *kauja-, an early borrowing of Latin cavea "hollow," from cavus "a hollow" (see cave (n.)).
coeducational (adj.): also co-educational, 1881, from co-education (1852), from co- + education.
coefficient (n.): also co-efficient, c.1600, from co- + efficient. Probably influenced by Modern Latin coefficiens, which was used in mathematics in 16c., introduced by French mathematician François Viète (1540-1603). As an adjective from 1660s.
coelacanth (n.): 1857, from Modern Latin Coelacanthus (genus name, 1839, Agassiz), from Greek koilos "hollow" (from PIE root *kel-; see cell) + akantha "spine" (see acrid). So called from the hollow fin rays supporting the tail. Known only as a fossil, the most recent one from 70 million years ago, until discovered living in the sea off the east coast of South Africa Dec. 22, 1938. The specimen was described by Marjorie Courtney-Latimer, who wrote about it to S.African ichthyologist J.L.B. Smith.
I stared and stared, at first in puzzlement. I did not know any fish of our own, or indeed of any seas like that; it looked more like a lizard. And then a bomb seemed to burst in my brain, and beyond that sketch and the paper of the letter, I was looking at a series of fishy creatures that flashed up as on a screen, fishes no longer here, fishes that had lived in dim past ages gone, and of which only fragmentary remains in rock are known. [J.L.B. Smith, "Old Fourlegs: The Story of the Coelacanth," 1956]
coeliac (adj.): 1660s, from Latin coeliacus, from Greek koiliakos "pertaining to the bowels," also "pain in the bowels," from koilia "bowels, abdominal cavity, intestines, tripe" from koilos "hollow," from PIE root *keue- "to swell; vault, hole" (see cumulus).
coelomate (n.): 1883, from Coelomata (1877), from Modern Latin neuter plural of coelomatus, from Greek koilomat- "hollow, cavity," from PIE root *kel- (see cell).
coeno-: word-forming element meaning "common," Latinized from Greek koinos "common, public, shared, general, ordinary," from PIE *kom "beside, near, by, with" (see com-).
coequal (adj.): late 14c.; see co- + equal.
coerce (v.): mid-15c., cohercen, from Middle French cohercer, from Latin coercere "to control, restrain, shut up together," from com- "together" (see co-) + arcere "to enclose, confine, contain, ward off," from PIE *ark- "to hold, contain, guard" (see arcane). Related: Coerced; coercing. No record of the word between late 15c. and mid-17c.; its reappearance 1650s is perhaps a back-formation from coercion.
coercion (n.): early 15c., from Old French cohercion (Modern French coercion), from Medieval Latin coercionem, from Latin coerctionem, earlier coercitionem, noun of action from past participle stem of coercere (see coerce).
coercive (adj.): c.1600, from coerce + -ive. Form coercitive (attested from 1630s) is more true to Latin.
coetaneous (adj.): "having the same age," c.1600, from Late Latin coaetanus "one of the same age," from com- "with, together with" (see co-) + aetat- "age" + adjectival suffix -aneus.
coeval (adj.): "having the same age," formed in English early 17c. from Late Latin coaevus, from Latin com- "equal" (see co-) + aevum "an age" (see eon). As a noun from c.1600.
coevolution (n.): also co-evolution, 1965, from co- + evolution; supposedly introduced by Paul Ehrlich and Peter Raven in a study of the relationship between caterpillars and plants.
coexist (v.): 1670s, from co- + exist. Of political/economic systems (especially with reference to communism and the West) from 1931. Related: Coexisted; coexisting.
coexistence (n.): also co-existence, mid-15c., "joint existence;" see co- + existence. As "peaceful relations between states of different ideologies," 1954, a Cold War term.
coextensive (adj.): 1771, from co- + extensive.
coffee (n.): c.1600, from Italian caffe, from Turkish kahveh, from Arabic qahwah "coffee," said originally to have meant "wine," but perhaps rather from Kaffa region of Ethiopia, a home of the plant (coffee in Kaffa is called buno, which was borrowed into Arabic as bunn "raw coffee"). Much initial diversity of spelling, including chaoua.

Yemen was the first great coffee exporter and to protect its trade decreed that no living plant could leave the country. In 16c., a Muslim pilgrim brought some coffee beans from Yemen and raised them in India. Appeared in Europe (from Arabia) c.1515-1519. Introduced to England by 1650, and by 1675 the country had more than 3,000 coffee houses. Coffee plantations established in Brazil 1727. Meaning "a light meal at which coffee is served" is from 1774. Coffee break attested from 1940s. Coffee pot from 1705.
coffer (n.): mid-13c., from Old French cofre "a chest" (12c., Modern French coffre), from Latin cophinus "basket" (see coffin).
coffin (n.): early 14c., "chest or box for valuables," from Old French cofin "sarcophagus," earlier "basket, coffer" (12c., Modern French coffin), from Latin cophinus "basket, hamper" (source of Italian cafano, Spanish cuebano "basket"), from Greek kophinos "a basket," of uncertain origin.

Funeral sense in English is 1520s; before that it was the literal Latin one and had also a meaning of "pie crust" (late 14c.). Meaning "vehicle regarded as unsafe" is from 1830s. Coffin nail "cigarette" is slang from 1880; nail in (one's) coffin "thing that contributes to one's death" is from 1792.
cog (n.): c.1300, "cog wheel;" late 14c., "tooth on a wheel," probably a borrowing from a Scandinavian language (cf. Norwegian kugg "cog") and cognate with Middle High German kugel "ball."
cogency (n.): 1680s, from cogent + -cy.
cogenial (adj.): 1774, variant of congenial.
cogent (adj.): 1650s, from French cogent "necessary, urgent" (14c.), from Latin cogentem (nominative cogens), present participle of cogere "to curdle; to compel; to collect," literally "to drive together," from com- "together" (see co-) + agere "to drive" (see act (n.)).
cogitate (v.): late 16c., from Latin cogitatus, past participle of cogitare "to think" (see cogitation). Related: Cogitated; cogitating.
cogitation (n.): c.1200, "thought, idea, notion," from Old French cogitacion "thought, consideration, reflection," from Latin cogitationem (nominative cogitatio), noun of action from past participle stem of cogitare "to think, reflect, consider, turn over in the mind," apparently from co-agitare, from com- "together" (see co-) + agitare, here in a sense of "to turn over in the mind," literally "to put in constant motion, drive, impel," frequentative of agere "to move, drive" (see agitation).
cogitative (adj.): late 15c., from Old French cogitatif (14c.), from Medieval Latin cogitativus, from Latin cogitare (see cogitation).
cognac (n.): 1590s, Coniacke, "wine produced in Cognac," the region in western France. The sense of "brandy" is 1755, shortened from 17c. cognac brandy, which was distilled from cognac wine. The place name is from Medieval Latin Comniacum, from the personal name Cominius and the Gallo-Roman suffix -acum.
cognate (adj.): 1640s, from Latin cognatus "of common descent," from com- "together" (see co-) + gnatus, past participle of gnasci, older form of nasci "to be born" (see genus). Words that are cognates are cousins, not siblings. As a noun, from 1754.
cognisance (n.): alternative spelling of cognizance (q.v.); also see -ize.
cognisant (adj.): alternative spelling of cognizant (q.v.); also see -ize.
cognition (n.): mid-15c., "ability to comprehend," from Latin cognitionem (nominative cognitio) "a getting to know, acquaintance, knowledge," noun of action from past participle stem of cognoscere (see cognizance).
cognitive (adv.): 1580s, from Latin cognit-, past participle stem of cognoscere (see cognizance) + -ive. Taken over by psychologists and sociologists after c.1940. Related: Cognitively.
cognitive dissonance (n.): 1957, developed and apparently coined by U.S. social psychologist Leon Festinger (1919-1989).