circumscribed circle

The circumcircle is a triangle's circumscribed circle, i.e., the unique circle that passes through each of the triangle's three vertices. The center O of the circumcircle is called the circumcenter, and the circle's radius R is called the circumradius. A triangle's three perpendicular bisectors M_A, M_B, and M_C meet at O. The Steiner point S and Tarry point T lie on the circumcircle. A circumcircle of a polygon is the two-dimensional case of a circumsphere of a solid.

Cevian circle | circle | circumcenter | circumradius | circumsphere | enclosing circle | excircles | incircle | minimal enclosing circle | Parry point | pivot theorem | Purser's theorem | Simson line | Steiner points | Tarry point