Definition:Polar of Point/Circle/Pole

Definition
Let $\CC$ be a circle whose radius is $r$ and whose center is at the origin of a Cartesian plane.

Let $P = \tuple {x_0, y_0}$ be an arbitrary point in the Cartesian plane. Let $\LL$ be the polar of $P$.

Then $P$ is known as the pole of $\LL$.

Also see

 * Definition:Polar of Point