noun Date: 1570 an angle that for a given dihedral angle is formed by two intersecting lines each of which lies on a face of the dihedral angle and is perpendicular to the edge of the face
PLANE ANGLE
Meaning of PLANE ANGLE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012