Noon \NOON\ , noun;
2. Twelve o'clock in the daytime
3. The highest, brightest, or finest point or part
The origin of noon is ultimately Latin nona hora, which meant "ninth hour," meaning the ninth hour of daylight, or 3pm. The Old English form, non, kept the meaning of "3 o'clock p.m." During the 12th century the meaning began to shift either because the time for Church prayers shifted from the ninth hour to the sixth hour, or because the time people ate their midday meal changed, or both. The shift was completed by the 14th century and the meaning has stayed the same ever since.