面めん角かく

noun

face angle

Mathematical term for the angle between two faces of a polyhedron or between a face and a reference plane. Compare 平面角 (plane angle).

See also: 平面角

• 正せい四し面めん体たいの面めん角かくは約やく70.53度どである。

  The face angle of a regular tetrahedron is approximately 70.53 degrees.