OK, here goes the explanation. (If you've just arrived, please refer to the previous post)
Clue1: One of the unlikely though interesting origins of OK is in the grading of woods used for furniture. The best oak goes as "Oak A" :)
Clue2: This is supposedly the most likely of the origins. Around 1830's Bostonian newspapers were full of these fashionable abbreviations (like R.T.B.S = Remains To Be Seen) that became increasingly popular with the readers. The abbreviation craze went so far as to produce abbreviations of intentional misspellings. No Go became K.G. (Know Go) and All Correct became O.K. (Oll Korrect), the joke being that neither the O nor the K was correct. Most of these abbrevaitions are believed to have gained currency in those times but only O.K. spread and survived.
Clue3: In 1840, OK was a slogan of the Democratic Party for President Martin Van Buren's reelection campaign. Named after his birthplace, Old Kinderhook, New York. "O.K. clubs" supporting him were established throughout the country. Old Kinderhook lost, but O.K. won a permanent place in American English.
Clue4: Haitian port called "Aux Cayes" (pronounced as aw-kay) . French fishermen might sometimes have used the phrase "au quai", literally "to the quay", to mean that a fishing trip was successful (or went okay)
Abhishek's comment led to further research and another theory that in World War II the term "zero killed" was used when a unit suffered no casualties in combat, and that this was then shortened to 0K. This proposed etymology is grossly anachronistic, since by this time the term had been widely used for a full century. The same theory has also been applied to the Civil War, but this is also anachronistic.
Hope I got it Waaw-kay!!! :)
Sources: The Merriam-Webster Book of Word Histories, www.answers.com
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