Definition:Circumcircle of Triangle

Definition

The circumcircle of a triangle is the circle that passes through all three of the triangle's vertices.

This circle is said to circumscribe the triangle.

Circumcenter

The center of a circumcircle of a triangle is called a circumcenter of a triangle.

Circumradius

A radius of a circumcircle of a triangle is called a circumradius of a triangle.

In the above diagram, $R$ is a circumradius.

Also see

• Definition:Incircle of Triangle
• Definition:Excircle of Triangle

• Triangle has Unique Circumcircle

• Results about circumcircles of triangles can be found here.

Sources

• 2014: Christopher Clapham and James Nicholson: The Concise Oxford Dictionary of Mathematics (5th ed.) ... (previous) ... (next): circumcircle