Geometry Circle Vocabulary

Front

What is the part of the circle highlighted in red called?

Back

semi-circle arc

Front

A segment whose endpoints lie on a circle is a _______.

Back

chord

Front

An arc is a smaller piece of the...

Back

Circumference

Front

What is this called? (Image of a radius)

Back

Radius

Front

Point C is...

Back

On the circle

Front

What is the longest chord in a circle called?

Back

Diameter

Front

What do you call a line that touches a circle at exactly one point?

Back

Tangent

Front

What is the angle formed at the center of the circle by two radii called?

Back

Central Angle

Front

What is the distance around a circle called?

Back

Circumference

Front

What is the formula for the circumference of a circle?

Back

C = 2πr or C = πd