zenithal-projectionhttp://www.oed.com/dictionary/zenithal-projection_n%3Ftab%3Dmeaning_and_usezenithal projection, n.
Revised 2018

zenithal projectionnoun

  1. 1877–
    Any of a class of map projections in which a portion of the globe is projected on to a plane tangential to a point on that portion, usually made the centre of the map; also called azimuthal projection.
    Common forms are the zenithal (or azimuthal) equal-area projection, devised by the Swiss mathematician Johann Heinrich Lambert in 1772, and the zenithal (or azimuthal) equidistant projection.
    1. 1877
      Lambert's Zenithal Projection resulted in a far less amount of distortion than those of Sanson or Bonne.
      Geogr. Magazine March 81/2
    2. 1882
      The name zenithal projections is..derived from the fact that they can always be considered as the representation of the hemisphere situated above the horizon of the given point, and having the zenith for pole.
      T. Craig, Treat. on Projections v. 89
    3. 1974
      Gnomic map, type of zenithal projection in which the Earth's grid is projected by radials from a point at the centre of the sphere into a tangent plane so that all great circles are represented by straight lines.
      Encyclopædia Britannica Micropædia vol. IV. 587/3
    4. 2004
      We derive the exact..transformations for the zenithal projections most commonly used in astronomy.
      Publications of Astronomical Society of Pacific vol. 116 971/1

Originally published as part of the entry for zenithal, adj.

zenithal, adj. was revised in June 2018.