| an angle formed by three or more planes intersecting in a common point or formed at the vertex of a cone. |
| solid angle n. An angle formed by three or more planes intersecting at a common point. |
| solid angle
A three-dimensional angle, formed by three or more planes intersecting at a common point. Its magnitude is measured in steradians, a unitless measure. The corner of a room forms a solid angle, as does the apex of a cone; one can imagine an indefinite number of planes forming the smooth round surface of the cone all intersecting at the apex. Solid angles are commonly used in photometry. |