| 释义 |
ˈzenithal, a.
[f. zenith + -al1.]
Pertaining or relating to, situated or occurring at, the zenith; also fig. supreme, ‘culminating’. zenithal projection, 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, usu. made the centre of the map.
1860Tyndall Glac. i. v. 39 The deep zenithal blue. 1869Dunkin Midn. Sky 57 Beta and Gamma Draconis..were the two zenithal stars in June. 1882T. Craig Treat. on Projections v. 89 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. 1891Hardy Tess xxv, A zenithal paradise, a nadiral hell. 1903Blackw. Mag. Nov. 651/1 They have known the zenithal instant of piscatorial life. 1910, etc. [see projection n. 7 b]. 1961L. F. Brosnahan Sounds of Language iii. 74 A continuous distribution of the O blood-group gene frequencies in Europe was..redrawn on a map of zenithal equal-area projection. 1974Encycl. Brit. Micropædia IV. 587/3 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. |