Online Etymology Dictionary

crag (n.): early 14c.; as a place-name element attested from c.1200, probably from a Celtic source akin to Old Irish crec "rock," and carrac "cliff," Welsh craig "rock, stone," Manx creg.
craggy (adj.): mid-15c.; see crag + -y (2).
cram (v.): Old English crammian "press something into something else," from Proto-Germanic *kram-/*krem- (cf. Old High German krimman "to press, pinch," Old Norse kremja "to squeeze, pinch"), from PIE root *ger- "to gather" (cf. Sanskrit gramah "heap, troop," Old Church Slavonic gramota "heap," Latin gremium "bosom, lap"). Meaning "study intensely for an exam" originally was British student slang first recorded 1803. Related: Crammed; cramming.
cramp (n.1): "muscle contraction," late 14c., from Old French crampe, from a Frankish or other Germanic word (cf. Old High German krapmhe "cramp, spasm," related to kramph "bent, crooked"), from a Proto-Germanic root forming many words for "bent, crooked," including, via French, crampon. Writer's cramp is first attested 1842 as the name of a physical affliction of the hand, in reference to translations of German medical papers (Stromeyer); also known as scrivener's palsy.
cramp (n.2): "metal bar bent at both ends," early 15c., from Middle Dutch crampe or Middle Low German krampe, both from the same Proto-Germanic root that yielded cramp (n.1). Metaphoric sense of "something that confines or hinders" first recorded 1719.
cramp (v.1): "to contract" (of muscles), early 15c., from cramp (n.1). Related: Cramped; cramping.
cramp (v.2): c.1400, "to bend or twist," from cramp (n.2). Later "compress forcibly" (1550s), and, figuratively, "to restrict" (1620s). Related: Cramped; cramping.
cranberry (n.): 1640s, American English adaptation of Low German kraanbere, from kraan "crane" (see crane (n.)) + Middle Low German bere "berry" (see berry). Perhaps so called from a resemblance between the plants' stamens and the beaks of cranes.

German and Dutch settlers in the New World apparently recognized the similarity between the European berries (Vaccinium oxycoccos) and the larger North American variety (V. macrocarpum) and transferred the name. In England, they were marshwhort or fenberries, but the North American berries, and the name, were brought over late 17c. The native Algonquian name for the plant is represented by West Abenaki popokwa.
crane (n.): Old English cran "large wading bird," common Germanic (cf. Old Saxon krano, Old High German krano, German Kranich, and, with unexplained change of consonant, Old Norse trani), from PIE *gere- (cf. Greek geranos, Latin grus, Welsh garan, Lithuanian garnys "heron, stork"), perhaps echoic of its cry. Metaphoric use for "machine with a long arm" is first attested late 13c. (a sense also in equivalent words in German and Greek).
crane (v.): "to stretch (the neck)," 1799, from crane (n.). Related: Craned; craning.
cranial (adj.): 1800, from Modern Latin cranium, from Greek kranion "skull" (see cranium) + -al (1).
cranio-: word-forming element meaning "of the brain," from Latinized comb. form of Greek kranion "skull" (see cranium).
craniotomy (n.): 1855, from cranio- + -tomy.
cranium (n.): 1540s, from Medieval Latin cranium, from Greek kranion "skull, upper part of the head," related to kara (poetic kras) "head," from PIE root *ker- "horn, head" (see horn (n.)). Strictly, the bones which enclose the brain.
crank (n.): Old English *cranc, implied in crancstæf "a weaver's instrument," crencestre "female weaver, spinster," from Proto-Germanic base *krank-, and related to crincan "to bend, yield" (see crinkle, cringe). English retains the literal sense of the ancient root, while German and Dutch krank "sick," formerly "weak, small," is a figurative use.

The sense of "an eccentric person," especially one who is irrationally fixated, is first recorded 1833, said to be from the crank of a barrel organ, which makes it play the same tune over and over; but more likely a back-formation from cranky (q.v.). Meaning "methamphetamine" attested by 1989.
crank (v.): 1590s, "to zig-zag," from crank (n.). Meaning "to turn a crank" is first attested 1908, with reference to automobile engines. Related: Cranked; cranking.
crankshaft (n.): 1854, from crank (v.) + shaft (n.). The basic form of the mechanism appears to date from Roman times.
cranky (adj.): "cross-tempered, irritable," 1807, from crank (n.) + -y (2). The evolution would be from earlier senses of crank, e.g. "a twist or fanciful turn of speech" (1590s); "inaccessible hole or crevice" (1560s). Grose's 1787 "Provincial Glossary" has "Cranky. Ailing sickly from the dutch crank, sick." and identifies it as a Northern word. Related: Crankily; crankiness.
Ben. Dang it, don't you spare him--A cross grain'd cranky toad as ever crawl'd. (etc.) [Richard Cumberland, "Lovers Resolutions," Act I, 1813]
cranny (n.): mid-15c., possibly from a diminutive of Middle French cran "notch, fissure" (14c.), from crener "to notch, split," from Medieval Latin crenare, possibly from Latin cernere "to separate, sift" (see crisis). But OED casts doubt on this derivation.
crap (v.): "defecate," 1846, from one of a cluster of words generally applied to things cast off or discarded (e.g. "weeds growing among corn" (early 15c.), "residue from renderings" (late 15c.), underworld slang for "money" (18c.), and in Shropshire, "dregs of beer or ale"), all probably from Middle English crappe "grain that was trodden underfoot in a barn, chaff" (mid-15c.), from Middle French crape "siftings," from Old French crappe, from Medieval Latin crappa, crapinum "chaff." Related: Crapped; crapping.

Despite folk etymology insistence, not from Thomas Crapper (1837-1910) who was, however, a busy plumber and may have had some minor role in the development of modern toilets. The name Crapper is a northern form of Cropper (attested from 1221), an occupational surname, obviously, but the exact reference is unclear.
crap (n.): "act of defecation," 1898; see crap (v.). Sense of "rubbish, nonsense" also first recorded 1898.
crape (n.): 1630s, Englished spelling of crepe (q.v.).
crappie (n.): type of freshwater fish, 1856, American English, of unknown origin; perhaps from Canadian French dialectal crappé.
crappy (adj.): 1846, from crap (n.) + -y (2). Related: Crappily; crappiness.
craps (n.): 1843, American English, unrelated to the term for excrement, instead it is from Louisiana French craps "the game of hazard," from an 18c. continental French corruption of English crabs, which was 18c. slang for "a throw of two or three" (the lowest throw), which perhaps is from crab (n.2), the sense in crab apple. The 1843 citation (in an anti-gambling publication) calls it "a game lately introduced into New Orleans."
crapulent (adj.): 1650s, from Latin crapulentus "very drunk," from crapula "excessive drinking" (see crapulous). Related: Crapulence.
crapulous (adj.): 1530s, "sick from too much drinking," from Latin crapula, from Greek kraipale "hangover, drunken headache, nausea from debauching." The Romans used it for drunkenness itself. English has used it in both senses. Related: Crapulously; crapulousness.
crash (v.): c.1400, crasschen "break in pieces;" with no identifiable ancestors or relatives it probably is imitative. Computing sense is 1973, which makes it one of the earliest computer jargon words. Meaning "break into a party, etc." is 1922. Slang meaning "to sleep" dates from 1943; especially from 1965. Related: Crashed; crashing.
crash (n.): 1570s, from crash (v.); sense of "financial collapse" is from 1817, "collision" is from 1910; references to falling of airplanes are from World War I.
crass (adj.): 1540s, from Middle French crasse (16c.), from Latin crassus "solid, thick, fat; dense." The literal sense always has been rare in English; meaning "grossly stupid" is recorded from 1650s, from French. Related: Crassly; crassness.
crate (n.): "large box," 1680s, earlier "hurdle, grillwork" (late 14c.), from Latin cratis "wickerwork, lattice, kitchen-rack," or from Dutch krat "basket;" both perhaps from a common PIE root *kert- "to turn, entwine" (see hurdle (n.)).
crate (v.): "to put in a crate," 1871, from crate (n.). Related: Crated; crating.
crater (n.): 1610s, from Latin crater, from Greek krater "bowl for mixing wine with water," from kera- "to mix," from PIE root *kere-. Used in Latin for bowl-shaped mouth of a volcano. Applied to features of the Moon since 1860. As a verb, from 1830 in poetry, 1872 in science. Related: Cratered; cratering.
cravat (n.): 1650s, from French cravate (17c.), from Cravate "Croatian," from German Krabate, from Serbo-Croatian Hrvat "a Croat" (see Croat). Cravats came into fashion 1650s in imitation of linen scarves worn by Croatian mercenaries in the French army in the Thirty Years War.
crave (v.): Old English crafian "ask, implore, demand by right," from North Germanic *krabojan (cf. Old Norse krefja "to demand," Danish kræve, Swedish kräva); perhaps related to craft in its base sense of "power." Current sense "to long for" is c.1400, probably through intermediate meaning "to ask very earnestly" (c.1300). Related: Craved; craving.
craven (adj.): early 13c., cravant, perhaps from Old French crevante "defeated," past participle of cravanter "to strike down, to fall down," from Latin crepare "to crack, creak." Sense affected by crave and moved from "defeated" to "cowardly" (c.1400) perhaps via intermediary sense of "confess oneself defeated." Related: Cravenly; cravenness.
cravings (n.): "urgent desires," 17c., from craving, verbal noun from crave.
craw (n.): Old English *cræg "throat," a Germanic word (e.g. Middle Dutch craghe "neck, throat," Old High German chrago, German Kragen "collar, neck"), of obscure origin.
crawfish (n.): 1620s, generally dismissed by British etymologists as a 19c. American English variant of crayfish, but perhaps it existed in Middle English. Also in 19c. American English as a verb, "to back out," in reference to the creature's movements.
crawl (v.): c.1200, creulen, from a Scandinavian source, perhaps Old Norse krafla "to claw (one's way)," from the same root as crab (n.1). If there was an Old English *craflian, it has not been recorded. Related: Crawled; crawling.
crawl (n.): 1818, from crawl (v.); in the swimming sense from 1903, the stroke developed by Frederick Cavill, well-known English swimmer who emigrated to Australia and modified the standard stroke of the day after observing South Seas islanders. So called because the swimmer's motion in the water resembles crawling.
crayfish (n.): "small, freshwater lobster," early 14c., crevis, from Old French crevice "crayfish" (13c., Modern French écrevisse), probably from Frankish *krebitja or a similar Germanic word that is a diminutive form of the root of crab (n.1); e.g. Old High German krebiz "crab, shellfish," German Krebs. Modern spelling is 16c., under influence of fish (n.).
crayon (n.): 1640s, from French crayon "pencil" (16c.), originally "chalk pencil," from craie "chalk," from Latin creta "chalk, pipe-clay," of unknown origin. Not now considered to mean "Cretan earth," as once was believed.
craze (v.): mid-14c., crasen, craisen "to shatter," probably Germanic and perhaps ultimately from a Scandinavian source (e.g. Old Norse *krasa "shatter"), but entering English via an Old French form (cf. Modern French écraser). Original sense preserved in crazy quilt pattern and in reference to pottery glazing (1832). Mental sense perhaps comes via transferred sense of "be diseased or deformed" (mid-15c.), or it might be an image. Related: Crazed; crazing.
craze (n.): late 15c., "break down in health," from craze (v.) in its Middle English sense; this led to a noun sense of "mental breakdown," and by 1813 to the extension to "mania, fad," or, as "The Century Dictionary" (1902) defines it, "An unreasoning or capricious liking or affectation of liking, more or less sudden and temporary, and usually shared by a number of persons, especially in society, for something particular, uncommon, peculiar, or curious ...."
craziness (n.): c.1600, "infirmity," from crazy + -ness. Meaning "state of being flawed or damaged" is from 1660s; that of mental unsoundness" is from 1755.
crazy (adj.): 1570s, "diseased, sickly," from craze + -y (2). Meaning "full of cracks or flaws" is from 1580s; that of "of unsound mind, or behaving as so" is from 1610s. Jazz slang sense "cool, exciting" attested by 1927. To drive (someone) crazy is attested by 1873. Phrase crazy like a fox recorded from 1935. Crazy Horse, Teton Lakhota (Siouan) war leader (d.1877) translates thašuka witko, literally "his horse is crazy."
creak (v.): early 14c., "utter a harsh cry," of imitative origin. Used of the sound made by a rusty gate hinge, etc., from 1580s. Related: Creaked; creaking. As a noun, from c.1600.
creaky (adj.): 1834, from creak + -y (2). Related: Creakily; creakiness.
cream (n.): early 14c., creyme, from Old French cresme (13c., Modern French crème) "chrism, holy oil," blend of Late Latin chrisma "ointment" (from Greek khrisma "unguent;" see chrism) and Late Latin cramum "cream," which is perhaps from Gaulish. Replaced Old English ream. Re-borrowed 19c. from French as creme. Figurative sense of "most excellent element or part" is from 1580s. Cream-cheese is from 1580s.