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Why do we say “OK“?

Of all the words in the English language, “OK” is pretty new: It’s been used only for about 180 years.

Although it has become the most spoken word on the planet, it’s kind of a strange word. Sometimes it’s spelled out — “okay” — and sometimes just two letters are used: “OK.” Other times, periods are after each letter: “O.K.”

I’m a syntactician, which means I look at the structure of language. I also study words and how they change over time.

For example, the word “silly” used to mean “happy” and now means “foolish.” Sometimes new words develop, such as “stan,” which means a person who’s obsessed with a celebrity, and “exomoon,” a moon outside our solar system.

Linguists (people who study languages) don’t always know why these shifts happen. Usually they’re in response to social changes or scientific discoveries. But the largest dictionary of the English language, the Oxford English Dictionary, is always adding new words. In fact, it added 1,400 new words this June and will add more words two more times this year.

“OK,” whose earliest usage is 1839, according to the Oxford English Dictionary, generally means things are good or all right.

So why did people start to say “OK”?

We aren’t entirely sure. But some linguists point to how, in the early 19th century, humorous abbreviations were popular. Young people would write things such as “KG,” which stood for “know go,” an intentional misspelling of “no go,” when they meant something was impossible. It was a way to play with language.

Likewise, experts think “OK” probably emerged as an abbreviation of “oll korrect” — which was a jokey way of saying “all correct.” Others say that it derives from “Old Kinderhook,” a nickname for 19th-century U.S. president Martin Van Buren, or that it comes from Choctaw, a Native American language.

The nice thing about “OK” is that it’s so versatile. It can be used as a noun, a verb, an adjective, a conjunction or an interjection. It has also competed, over time, with “alright” and “all right” — words and phrases that have identical meanings.

One last important fact: If you like to play Scrabble, it’s all right — and even OK — to use “OK” when playing. Just within the past year, it became an accepted word.

Elly van Gelderen is a professor at Arizona State University. This article was originally published at theconversation.com .