cpuyoudaoicibaDictYouDict[cpu 词源字典]
by 1970, abbreviation of central processing unit.[cpu etymology, cpu origin, 英语词源]
crab (n.1)youdaoicibaDictYouDict
crustacean, Old English crabba, from a general Germanic root (compare Dutch krab, Old High German krebiz, German Krabbe, Old Norse krabbi "crab"), related to Low German krabben, Dutch krabelen "to scratch, claw," from PIE root *gerbh- "to scratch, carve" (see carve). The constellation name is attested in English from c. 1000; the Crab Nebula (1840), however, is in Taurus, the result of the supernova of 1054, and is so called for its shape. French crabe (13c.) is from Germanic, probably Old Norse.
crab (n.2)youdaoicibaDictYouDict
"fruit of the wild apple tree," c. 1300, crabbe, perhaps from Scandinavian (compare Swedish krabbäpple), of obscure origin. The combination of "bad-tempered, combative" and "sour" in the two nouns crab naturally yielded a verb meaning of "to vex, irritate" (c. 1400), later "to complain irritably, find fault" (c. 1500). The noun meaning "sour person" is from 1570s.
crabbed (adj.)youdaoicibaDictYouDict
late 14c., "peevish, angry, ill-tempered," from crab (n.1), from the crab's combative disposition; mid-15c. as "resembling a crab" in reference to crookedness. Of taste "bitter, harsh," late 14c., from crab (n.2).
crabby (adj.)youdaoicibaDictYouDict
1520s, in now-obsolete sense "crooked, gnarled, rough," from extended sense of crab (n.1) + -y (2). Meaning "disagreeable, sour, peevish" is attested from 1776, American English. Both senses were found earlier in crabbed.
crabgrass (n.)youdaoicibaDictYouDict
c. 1600, from crab (n.1) + grass. Originally a marine grass of salt marshes; modern meaning is from 1743. Perhaps partly for its crooked form.
crack (v.)youdaoicibaDictYouDict
Old English cracian "make a sharp noise," from Proto-Germanic *krakojan (cognates: Middle Dutch craken, Dutch kraken, German krachen), probably imitative. Related: Cracked; cracking. From early 14c. as "to utter, say, speak, talk," especially "speak loudly or boastingly" (late 14c.). To crack a smile is from 1835, American English; to crack the whip in the figurative sense is from 1886.
crack (n.)youdaoicibaDictYouDict
"a split, an opening," mid-15c., earlier "a splitting sound; a fart; the sound of a trumpet" (late 14c.), probably from crack (v.). Meaning "rock cocaine" is first attested 1985. The superstition that it is bad luck to step on sidewalk cracks has been traced to c. 1890. Meaning "try, attempt" first attested 1830, nautical, probably a hunting metaphor, from slang sense of "fire a gun."
At their head, apart from the rest, was a black bull, who appeared to be their leader; he came roaring along, his tail straight an end, and at times tossing up the earth with his horns. I never felt such a desire to have a crack at any thing in all my life. He drew nigh the place where I was standing; I raised my beautiful Betsey to my shoulder, took deliberate aim, blazed away, and he roared, and suddenly stopped. ["A Narrative of the Life of David Crockett, Written by Himself," Philadelphia, 1834]
Adjectival meaning "top-notch, superior" (as in a crack shot) is slang from 1793, perhaps from earlier verbal sense of "do any thing with quickness or smartness" (Johnson). Grose (1796) has "THE CRACK, or ALL THE CRACK. The fashionable theme, the go." To fall through the cracks figuratively, "escape notice," is by 1975.
crackdown (n.)youdaoicibaDictYouDict
also crack down; 1935, from the verbal phrase (1915), from crack (v.) + down (adv.); probably from the sense of "to shoot at" (1913).
These scab contractors probably think that they have us whipped, but they are badly mistaken. With the reorganization of the Building Trades Council, which is progressing nicely, we will be in a position to cope with them and when we do crack down on them they will have to come across or get out. ["Journal of Electrical Workers and Operators," September 1915]
cracked (adj.)youdaoicibaDictYouDict
mid-15c., past participle adjective from crack (v). Meaning "mentally unsound" is 17c. (compare crack-brain "crazy fellow"). The equivalent Greek word was used in this sense by Aristophanes.
cracker (n.1)youdaoicibaDictYouDict
mid-15c., "hard wafer," but the specific application to a thin, crisp biscuit is 1739; agent noun from crack (v.). Cracker-barrel (adj.) "emblematic of down-home ways and views" is from 1877.
cracker (n.2)youdaoicibaDictYouDict
Southern U.S. derogatory term for "poor, white trash" (1766), probably an agent noun from crack (v.) in the sense "to boast" (as in not what it's cracked up to be). Compare Latin crepare "to rattle, crack, creak," with a secondary figurative sense of "boast of, prattle, make ado about."
I should explain to your Lordship what is meant by crackers; a name they have got from being great boasters; they are a lawless set of rascalls on the frontiers of Virginia, Maryland, the Carolinas and Georgia, who often change their places of abode. [1766, G. Cochrane]
But DARE compares corn-cracker "poor white farmer" (1835, U.S. Midwest colloquial). Especially of Georgians by 1808, though often extended to residents of northern Florida. Another name in mid-19c. use was sand-hiller "poor white in Georgia or South Carolina."
Not very essentially different is the condition of a class of people living in the pine-barrens nearest the coast [of South Carolina], as described to me by a rice-planter. They seldom have any meat, he said, except they steal hogs, which belong to the planters, or their negroes, and their chief diet is rice and milk. "They are small, gaunt, and cadaverous, and their skin is just the color of the sand-hills they live on. They are quite incapable of applying themselves steadily to any labor, and their habits are very much like those of the old Indians." [Frederick Law Olmsted, "A Journey in the Seaboard Slave States," 1856]
cracker-jack (n.)youdaoicibaDictYouDict
also crackerjack, "something excellent," 1893, U.S. colloquialism, apparently a fanciful construction, earliest use in reference to racing horses. The caramel-coated popcorn-and-peanuts confection was said to have been introduced at the World's Columbian Exposition (1893). Supposedly a salesman gave it the name when he tasted some and said, "That's a cracker-jack," using the then-popular expression. The name was trademarked 1896. The "Prize in Every Box" was introduced 1912.
"Your brother Bob is traveling, isn't he?"
"Yep. He's with one of the big racing teams. I tell you, he's a cracker-jack! Wins a bushel of diamonds and gold cups every week."
["Life," Aug. 1, 1895]
crackhead (n.)youdaoicibaDictYouDict
slang, "crack cocaine addict," by 1986, from crack (n.) in the drug slang sense + head (n.). In earlier slang, crack-headed meant "crazy" (1796), from the literal sense of crack.
cracking (adj.)youdaoicibaDictYouDict
"excellent," colloquial from 1830s, from present participle of crack (v.).
crackle (v.)youdaoicibaDictYouDict
mid-15c., crackelen, frequentative of cracken "to crack" (see crack (v.)). Related: Crackled; crackling. The noun is recorded from 1833.
crackpot (n.)youdaoicibaDictYouDict
"mentally unbalanced person," 1898, probably from crack (v.) + pot (n.1) in a slang sense of "head." Compare crack-brain "crazy fellow" (late 16c.). Earlier it was used in a slang sense "a small-time big-shot" (1883), and by medical doctors in reference to a "metallic chinking sometimes heard when percussion is made over a cavity which communicates with a bronchus."
cradle (n.)youdaoicibaDictYouDict
"baby's bed," c. 1200, cradel, from Old English cradol "little bed, cot," from Proto-Germanic *kradulaz "basket" (cognates: Old High German kratto, krezzo "basket," German Krätze "basket carried on the back"). From late 14c. as "device for holding or hoisting." Cat's cradle is so called from 1768. Cradle-snatching "amorous pursuit of younger person" is from 1906.
"It's like cradle-snatching to want to marry a girl of sixteen, and you ought to be ashamed of yourself, for you can't be much more than twenty one yourself." ["Edith Van Dyne" (L. Frank Baum), "Aunt Jane's Nieces Abroad," 1906]
cradle (v.)youdaoicibaDictYouDict
c. 1500, from cradle (n.). Related: Cradled; cradling.
craft (n.)youdaoicibaDictYouDict
Old English cræft (West Saxon, Northumbrian), -creft (Kentish), originally "power, physical strength, might," from Proto-Germanic *krab-/*kraf- (cognates: Old Frisian kreft, Old High German chraft, German Kraft "strength, skill;" Old Norse kraptr "strength, virtue"). Sense expanded in Old English to include "skill, dexterity; art, science, talent" (via a notion of "mental power"), which led by late Old English to the meaning "trade, handicraft, calling," also "something built or made." The word still was used for "might, power" in Middle English.

Use for "small boat" is first recorded 1670s, probably from a phrase similar to vessels of small craft and referring either to the trade they did or the seamanship they required, or perhaps it preserves the word in its original sense of "power."