# Sphere

## DEFINITION

A three-dimensional form shaped like a ball, circular from all possible points of view. Its surface consists of points, all of which are the same distance (radius) from its center. Refers both to the surface and to the space it encloses. The mathematical formula with which to calculate the area of the surface of a sphere: multiply four times the product of pi times the radius squared. The volume of a sphere: 4/3 (or 1.333) times the product of pi times the radius cubed. "Sphere" may also refer to the extent of a person's knowledge, interests, or social position; or, one's domain; area of power, control, or influence.Spheres are among the ten classes of patterns.Also see circle, cone, concave, conglobe, convex, cylinder, hemisphere, Op Art, ovoid, penumbra, pyramid, and spheroid.