n.
Pronunciation: m ə - ' ri-d ē - ə n
Function: noun
Etymology: Middle English, from Anglo-French meridien, from meridien of noon, from Latin meridianus, from meridies noon, south, irregular from medius mid + dies day ― more at MID , DEITY
Date: 14th century
1 archaic : the hour of noon : MIDDAY
2 : a great circle of the celestial sphere passing through its poles and the zenith of a given place ― see AZIMUTH illustration
3 : a high point
4 a (1) : a great circle on the surface of the earth passing through the poles (2) : the half of such a circle included between the poles b : a representation of such a circle or half circle numbered for longitude on a map or globe ― see LONGITUDE illustration
5 : any of the pathways along which the body's vital energy flows according to the theory behind acupuncture
– meridian adjective