Circumscribable polytope

A polytope is said to be circumscribable when all of its vertices are at a common distance from a point. This point is known as the circumcenter, and the distance is known as the circumradius. In Euclidean space, all points at the circumradius' distance from the circumcenter define a hypersphere, known as the circumsphere of the polytope.

Every finite isogonal polytope in Euclidean space is circumscribable, its center being the unique fixed point of its symmetry group. Orbiform polytopes provide a further class of circumscribable polytopes.