Definition

The angle at the centre of a sphere which is tangent to the SPHEROID along the GEODETIC EQUATOR, between the plane of the EQUATOR and the radius to the point inter­sected on the sphere by a straight line perpendicular to the plane of the EQUA­TOR and passing through the point on the SPHEROID whose parametric latitude is defined. Parametric latitude is an auxiliary LATITUDE used in problems of GEODESY and CARTOGRAPHY. Also calledreduced latitu­de, geometric latitudeor eccentric angle.