I have been told that the term "OK" originates from the Royal Observatory at Kew in West London. It was here that all marine timepieces were mended and recalibrated to mean time. Each chronometer was then stamped "Observatory Kew" or OK to show that it had been checked and was safe to use. And so the term OK was created to mean something correct. It was at the Observatory Kew that King George III ran a series of unbiased trials of the John Harrison marine timepieces during the infamous Longitude prize. The Observatory is still there today, though it is no longer used as an observatory.