An ellipse
A diameter bisects a circle.
A tangent. And it does not need to be a circle - it can be any curve.
A Circle
radius
An ellipse, sometimes referred to as an oval.
The name of a squashed circle is an oval
An ellipse
A diameter bisects a circle.
radius
A tangent. And it does not need to be a circle - it can be any curve.
It is a tangent
radius
A Circle
radius
It is the radius
Tangent.