noun
central angle
Geometry term: the angle formed by two radii of a circle, with the vertex at the center.
扇形の中心角を求める公式を覚えていますか。
Do you remember the formula for finding the central angle of a sector?
An inscribed angle (vertex on the circumference), whereas 中心角 has its vertex at the center.
Compound of 中心 (center) and 角 (angle).