The circle which passes through all three vertices of a given triangle is called its circumcircle. It is said to circumscribe the triangle.
The centre of the circumcircle is called the circumcentre of the triangle.
![Triangle A B C with its circumcircle shown](/glossary/circumcircle/images/circumcircle.png)
The circle which passes through all three vertices of a given triangle is called its circumcircle. It is said to circumscribe the triangle.
The centre of the circumcircle is called the circumcentre of the triangle.