OK < all correct

xiao4zhu

The exclamation OK is first recorded in the mid 19th century. It is most probably an abbreviation of orl korrect, a humorous form of all correct, which was popularized as a slogan during US President Martin Van Buren's re-election campaign of 1840. The initials also represented his nickname Old Kinderhook, derived from his birthplace, Kinderhook in New York State.