solid angle
measure of a subtended portion of a sphere, used to describe the apparent size of items in a three-dimensional field of view
en-US/ˈsɑlɪd ˈæŋɡəl/
en-GB/ˈsɒlɪd ˈæŋɡəl/
measure of a subtended portion of a sphere, used to describe the apparent size of items in a three-dimensional field of view