OK

OK first appears clearly in print in Boston on March 23, 1839. The form O.K. was used as a playful abbreviation of oll korrect, a comic misspelling of "all correct." That fashion belonged to a brief craze for humorous initials in American newspapers. What lasted was this one small joke.

The abbreviation spread fast through print and politics. In 1840 supporters of President Martin Van Buren used OK clubs, playing on both the new expression and Van Buren's nickname Old Kinderhook. That campaign did not invent the word, but it helped make the letters widely visible. By the mid-19th century, O.K. was already familiar across the United States.

Once established, the expression loosened from its comic source. It came to mean acceptable, satisfactory, safe, or approved. Speakers also turned it into a verb, as in to OK a proposal, and later into the fuller spelling okay. The punctuation gradually fell away, leaving both OK and ok in ordinary use.

Its exact success came from usefulness rather than elegance. Few words can answer a question, grant permission, soften disagreement, and mark moderate quality all at once. By the 20th century, OK had spread far beyond American English into many other languages. What began as newsroom slang became one of the world's most portable words.