Had to post this by itself (it comes from the end of the yourDictionary.com lists):

Most frequently spoken word on the Planet:

O.K. Still one of the few examples where a person's initial's live on to become a word. (In this case, antebellum president Martin Van Buren, who was born in Old Kinderhook, New York; his nickname, Old Kinderhook, quickly evolved to O.K.) An alternate derivation suggests a play on the dialectal pronunciations of "all correct" by editors of the Boston Post in 1839.