It can often be very difficult to find the origins of words in the English language, but for OK, also spelled okay, we’re pretty sure we know exactly where it came from. O.K. was originally an abbreviation for “all correct”. Obviously the words “all correct” don’t start with an O or a K, but at the time it was quite trendy for young people to misspell words and then abbreviate them. It would have been misspelled as “oll korrect”. Other such abbreviations that were popular included “OW” for “oll wright”, “KG” for “know go” and “KY” for “know yuse”. So you don’t have to worry about all the crazy things kids say these days, it’s been going on for hundreds of years!
The abbreviation of O.K. was first published on March 23 1839 in the Boston Morning Post. Unlike those other phrases, OK obviously caught on, probably partially because it was used in Martin van Buren's campaign in the following year. At first it was mostly considered a slang term and many authors in the 1800s refused to use it in their works. Of course now it is such a commonly used phrase in our society that no one remembers it was once slang. It is one of the most commonly used words around the world and can even be found in other languages. Celebrate its birthday every year on March 23rd.