Circle

Arcs, chords, and semicircles

The terms radius of a circle, diameter of a circle and the circumference of a circle are not the only terms used to describe parts of the circle. Other terms are also commong for circles such as arc, chord, and semicircle.

Arc of a circle

An arc of a circle is a curved line drawn between two points along the circumference of a circle.

Arc of a circle

Chord of a circle

A chord of a circle is a line drawn between two points on a circle.

Chord of a circle

Semicircle

A semicircle is an arc that is defined by diametric points along the circle. This arc is as large as half (semi) the circle.

Semicircle