资料来源 : Webster's Revised Unabridged Dictionary (1913)

Quadrantal \Quad*ran"tal\, a. [L. quadrantalis containing the
   fourth fourth part of a measure.] (Geom.)
   Of or pertaining to a quadrant; also, included in the fourth
   part of a circle; as, quadrantal space.

   {Quadrantal triangle}, a spherical triangle having one side
      equal to a quadrant or arc of 90[deg].

   {Quadrantal versor}, a versor that expresses rotation through
      one right angle.