A line of constant longitude on a spheroid (or sphere). More generally, a meridian of a surface of revolution is the intersection of the surface with a plane containing the axis of revolution.
Meridian
See also
Latitude, Longitude, Surface of Revolution, Surface of Revolution ParallelExplore with Wolfram|Alpha
References
Gray, A. Modern Differential Geometry of Curves and Surfaces with Mathematica, 2nd ed. Boca Raton, FL: CRC Press, p. 238, 1997.Referenced on Wolfram|Alpha
MeridianCite this as:
Weisstein, Eric W. "Meridian." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Meridian.html