# Is there a term for these kinds of 3D angles?

So for 2D angles (radians), the measure of the angle is equal to length of the subtended arc of the unit circle.

Can we define 3D angles to be the area subtended by the angle on the unit sphere?

For example, the 3D angle measure of one corner of a cube is $1/8 \times 4\pi = 1/2\pi$