# Definition:Incircle of Triangle

## Contents

## Definition

The **incircle** of a triangle is the circle tangent to each side of the triangle.

This circle is said to be inscribed in the triangle.

### Incenter

The center of an incircle of a triangle is called an **incenter of the triangle**.

### Inradius

A radius of an incircle of a triangle is called an **inradius of the triangle**.

In the above diagram, $r$ is an inradius.