The daytime canonical hours of the Catholic Church take their names from the Roman clock: the prime, tercet, sext and none occur during the first (prime) = 6 am, third (tertian) = 9 am, sixth (sextan) = 12 pm, and ninth (none) = 3 pm, hours of the day. The English term noon is also derived from the ninth hour.
wall clock - a clock mounted on a wall. clock - a timepiece that shows the time of day.