I. mə̇ˈridēən noun
( -s )
Etymology: Middle English meridien, meridian, from Middle French meridien, from meridien, adjective
1.
a. obsolete : the hour of noon : midday
b. Scotland : a midday dram
2. : a great circle of the celestial sphere passing through its poles and the zenith of a given place
3.
a. archaic : the highest apparent point reached in the heavens by the sun or a star
b. : a high point (as of development or prosperity)
the problem of the unmarried don after he had passed the meridian — H.J.Laski
4.
a.
(1) : a great circle on the surface of the earth passing through the poles and any given place
(2) : the half of such a circle included between the poles with a plane coinciding with that of the astronomical meridian of the place — see prime meridian
b. : a representation of such a circle or half circle on a map or globe : any of a series of lines drawn at intervals due north and south or in the direction of the poles and numbered according to the degrees of longitude
the 90th meridian east of Greenwich
c. : a graduated circle (as of brass) in which a globe is suspended and revolves
5. archaic : special tastes, capacities, or conditions
suited the meridian of the … servants' hall — Washington Irving
6. or meridian curve : the curve formed by the intersection of a surface of revolution and a plane passing through the axis of revolution
7. : a line or circle (as on the globular shell of some sea urchins) resembling a meridian of longitude
II. adjective
Etymology: Middle English meridien, from Middle French, from Latin meridianus, from meridies noon, south (from meri- — alteration of medius mid — + dies day) + -anus -an — more at mid , deity
1. : being at or relating to midday : belonging to or passing through the highest point attained by a heavenly body in its diurnal course
2. : of or relating to a meridian
3.
a. : of or relating to a high point, crest, or culmination
the Roman people had arrived at their meridian glory — C.G.Bowers
b. obsolete : supremely excellent : consummate , extreme