ledgeryoudaoicibaDictYouDict[ledger 词源字典]
ledger: [15] Etymologically, a ledger is a book that ‘lies’ in one place. The term was used in 15th- and 16th-century English with various specific applications, including a ‘large copy of the Breviary’ (the Roman Catholic service book), and a ‘large register or record-book’ – both big volumes that would not have been moved around much – but it finally settled on the ‘main book in the set of books used for keeping accounts’. It probably comes from Dutch legger or ligger, agent nouns derived respectively from leggen ‘lay’ and liggen ‘lie’ (relatives of English lay and lie).
=> lay, lie[ledger etymology, ledger origin, 英语词源]
bone (v.)youdaoicibaDictYouDict
especially in bone up "study," 1880s student slang, probably from "Bohn's Classical Library," a popular series in higher education published by German-born English publisher Henry George Bohn (1796-1884) as part of a broad series of "libraries" he issued from 1846, totaling 766 volumes, continued after 1864 by G. Bell & Sons.
charade (n.)youdaoicibaDictYouDict
1776, from French charade (18c.), probably from Provençal charrado "long talk, chatter," of obscure origin, perhaps from charrar "to chatter, gossip," of echoic origin. Compare Italian ciarlare, Spanish charlar "to talk, prattle." Originally not silent, but relying rather on enigmatic descriptions of the words or syllables.
As we have ever made it a Rule to shew our Attention to the Reader, by 'catching the Manners living, as they rise,' as Mr. Pope expresses it, we think ourselves obliged to give Place to the following Specimens of a new Kind of SMALL WIT, which, for some Weeks past, has been the Subject of Conversation in almost every Society, from the Court to the Cottage. The CHARADE is, in fact, a near Relation of the old Rebus. It is usually formed from a Word of two Syllables; the first Syllable is described by the Writer; then the second; they are afterwards united and the whole Word marked out .... [supplement to "The Universal Magazine of Knowledge and Pleasure," volumes 58-59, 1776]
Among the examples given are:

My first makes all nature appear of one face;
At the next we find music, and beauty and grace;
And, if this Charade is most easily read,
I think that the third shou'd be thrown at my head.

[The answer is "snow-ball."]

The silent form, the main modern form, was at first a variant known as dumb charades and at first it was not a speed contest; rather it adhered to the old pattern, and the performing team acted out all the parts in order before the audience team began to guess.
There is one species of charade which is performed solely by "dumb motions," somewhat resembling the child's game of "trades and professions"; but the acting charade is a much more amusing, and more difficult matter. ["Goldoni, and Modern Italian Comedy," in "The Foreign And Colonial Quarterly Review," Volume 6, 1846]
An 1850 book, "Acting Charades," reports that Charades en Action were all the rage in French society, and that "Lately, the game has been introduced into the drawing-rooms of a few mirth-loving Englishmen. Its success has been tremendous." Welsh siarad obviously is a loan-word from French or English, but its meaning of "speak, a talk" is closer to the Provençal original.
DAEyoudaoicibaDictYouDict
initialism (acronym) for "A Dictionary of American English on Historical Principles," published in four volumes between 1936 and 1944, edited by Sir William A. Craigie and James R. Hulbert.
middle (adj.)youdaoicibaDictYouDict
Old English middel, from West Germanic *middila (cognates: Old Frisian middel, Old Saxon middil, Middle Low German, Dutch middel, Old High German mittil, German mittel), from Proto-Germanic *medjaz (see mid). Middle name attested from 1815; as "one's outstanding characteristic," colloquial, from 1911, American English.
According to Mr. H.A. Hamilton, in his "Quarter Sessions from Queen Elizabeth," the practice of giving children two Christian names was unknown in England before the period of the Stuarts, was rarely adopted down to the time of the Revolution, and never became common until after the Hanoverian family was seated on the throne. "In looking through so many volumes of county records," he says, "I have, of course, seen many thousands and tens of thousands of proper names, belonging to men of all ranks and degrees,--to noblemen, justices, jurymen, witnesses, sureties, innkeepers, hawkers, paupers, vagrants, criminals, and others,--and in no single instance, down to the end of the reign of Anne, have I noticed any person bearing more than one Christian name ...." [Walsh]
Middle school attested from 1838, originally "middle-class school, school for middle-class children;" the sense in reference to a school for grades between elementary and high school is from 1960. Middle management is 1957. Middle-of-the-road in the figurative sense is attested from 1894; edges of a dirt road can be washed out and thus less safe. Middle finger so called from c. 1000.
nineties (n.)youdaoicibaDictYouDict
1857 as the years of someone's life between 90 and 99; from 1848 as the tenth decade of years in a given century; 1849 with reference to Fahrenheit temperature. See ninety.
Many still live who remember those days; if the old men cannot tell you the exact date, they will say: 'It were in the nineties;' (etc.) ["Chambers's Journal," Nov. 1, 1856]
In Britain, the naughty nineties was a popular name 1920s-30s for the 1890s, based on the notion of a relaxing of morality and mood in contrast to earlier Victorian times. In U.S., gay nineties in reference to the same decade is attested from 1927, and was the title of a regular nostalgia feature in "Life" magazine about that time.
The long, dreary blue-law Sunday afternoons were periods of the Nineties which no amount of rosy retrospect will ever be able to recall as gay, especially to a normal healthy boy to whom all activities were taboo except G. A. Henty and the bound volumes of Leslie's Weekly of the Civil War. [Life, Sept. 1, 1927]
pool (n.2)youdaoicibaDictYouDict
game similar to billiards, 1848, originally (1690s) a card game played for collective stakes (a "pool"), from French poule "stakes, booty, plunder," literally "hen," from Old French poille "hen, young fowl" (see foal (n.)).

Perhaps the original notion is from jeu de la poule, supposedly a game in which people threw things at a chicken and the player who hit it, won it, which speaks volumes about life in the Middle Ages. The notion behind the word, then, is "playing for money." The connection of "hen" and "stakes" is also present in Spanish polla and Walloon paie.

Meaning "collective stakes" in betting first recorded 1869; sense of "common reservoir of resources" is from 1917. Meaning "group of persons who share duties or skills" is from 1928. From 1933 as short for football pool in wagering. Pool shark is from 1898. The phrase dirty pool "underhanded or unsportsmanlike conduct," especially in politics (1951), seems to belong here now, but the phrase dirty pool of politics, with an image of pool (n.1) is recorded from 1871 and was in use early 20c.