Meridian

Origin

From Middle English, from Old French, from Latin meridianus ("of or belonging to midday or to the south, southern"), from meridies ("midday, the south"), originally *medidies, from medius ("middle") + diēs ("day").

Full definition of meridian

Noun

1. An imaginary great circle on the Earth's surface, passing through the geographic poles.
2. Either half of such a great circle, all points of which have the same longitude.
3. (astronomy) A great circle passing through the poles of the celestial sphere and the zenith for a particular observer.
4. (mathematics) A similar line on any general surface of revolution.
5. (alternative medicine) Any of the pathways on the body along which the vital energy is thought to flow and, therefore, the acupoints are distributed.
6. The highest point, as of success, prosperity, etc.; culmination.
• ShakespeareI have touched the highest point of all my greatness,
  And from that full meridian of my glory
  I haste now to my setting.

Adjective

1. Meridional; relating to a meridian.
2. Relating to noon
3. Relating to the highest point or culmination.meridian splendour