これこそ、何が正しいかわかりませんね。 昔必要があって、調べたノートをコピーしました。 ごめんなさい、全て英語です。 これで、前に出ていた回答と比べることができると思います。
For years no one was really sure where the word came from. The origin of OK became the Holy Grail of etymology. Finally, in 1963 the Galahad of our story, Dr. Allen Walker Read of Columbia University appeared and uncovered the origin.
But first, some of the more popular suggestions as to the origin are as follows. These can all be dismissed because of lack of evidence or because OK predates the events that supposedly led to creation.
It stands for oll korrect, a misspelling of all correct, usually by a famous person, most often Andrew Jackson. This one comes close to the mark, but still misses it.
It stands for Old Kinderhook, the nickname of Martin Van Buren who came from Kinderhook, New York. Old Kinderhook played a role in popularizing the term, but it is not its origin. (More on this later.)
It comes from any one of a number of languages, most often the Choctaw word okeh . This explanation often involves Andrew Jackson again, but this time adopting it from the Indian language not because he was orthographically-challenged. A later president, Woodrow Wilson, favored this explanation, but he was wrong. As far as this explanation goes, it was not suggested until 1885 and no evidence exists that this, or any foreign word, is in fact the origin.
It is an abbreviation for Oberst Kommandant, or Colonel-in-Command, used by Von Steuben or Schliessen (take your pick) during the Revolutionary War. No record of either man, or anyone until 1839, using this phrase exists.
It comes from the French Aux Cayes, a port in Haiti famed for its rum.
It stood for Orrin Kendall crackers supplied to the Union Army during the Civil War. Unfortunately for Orrin's immortality, OK was in use twenty years before the Civil War.
It stood for Obadiah Kelly, a railroad shipping clerk akin to Kilroy who initialed bills of lading. And,
That it was an 1860s telegraph term for Open Key.
Of the above explanations, the first comes the closest to being true, but it too is false. Andrew Jackson was a notoriously poor speller. So much so that his spelling became an issue in the 1828 campaign. (Dan Quayle can take heart in the fact that he was not the first.) He is not, however, known to have ever used the expression OK or misspelled "all correct" with the two letters in question. The association of the word OK with Jackson, however, is not entirely without foundation. George W. Stimpson's Nuggets Of Knowledge, published in 1934 cites a 1790 court record from Sumner County, Tennessee in which Jackson "proved a bill of sale from Hugh McGary to Gasper Mansker, for a Negro man, which was O.K." This was probably just poor penmanship on the part of a court clerk, however. James Parton's biography of Jackson suggests that is really an illegible O.R., which was the abbreviation used for Order Recorded.
The incorrect spelling explanation is the correct one. Although the part about Andrew Jackson is almost certainly apocryphal. Allen Walker Read of Columbia University solved the mystery in a series of articles in American Speech in 1963-64. In 1839, a "frolicsome group," as Read describes them, called the Anti-Bell-Ringing Society in Boston started using the term to stand for oll korrect, a facetious misspelling.
The first recorded use of OK was in the spring of 1839 by the Boston Morning Post :
(23 March) "He of the Journal...would have the "contribution box," et ceteras, o.k.--all correct--and cause the corks to fly, like sparks, upward."
(26 March) "Had the pleasure of taking these 'interesting strangers' by the hand, and wishing them a speedy passage to the Commercial Emporium, They were o.k."
(10 April) "It is hardly necessary to say to those who know Mr. Hughes, that his establishment will be found to be 'A. No. One'--that is, O.K.--all correct."
By July of that year, the term spread south to New York, and quickly gained wide acceptance:
(27 July, Evening Tattler) "These 'wise men from the East'...are right...to play at bowls with us as long as we are willing to set ourselves up, like skittles, to be knocked down for their amusement and emolument. OK! all correct!"
The next year, 1840, New York Democrats formed an organization called the OK Club. The name of the club stood for Old Kinderhook as Martin Van Buren was running for reelection that year. Since the term was in use prior to the formation of the OK Club, it seems likely that the name of the club was due in part due to the phrase, not vice versa. The activities of the OK Club, however, undoubtedly contributed to the popularity of OK even if not providing the origin.
The variant A-OK first appeared during NASA's Mercury program of the 1960s. It may be a combination of A-One with OK. Tom Wolfe in The Right Stuff, however, claims that it was originally used by Shorty Powers, the "Voice of Mercury Control," in radio transmissions because the "A" sound cut through static better than the "O".
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