Meridians

noun

1. The south.
2. Midday, noon.
3. A great circle passing through the poles of the celestial sphere and the zenith for a particular point on the earth's surface.
4. An imaginary great circle on the Earth's surface, passing through the geographic poles, or that half of such a circle extending from pole to pole, all points of which have the same longitude.
5. The highest or most developed point of something; culmination, splendour.