Definition:Epicycle of Epicycloid/Also known as

Epicycle of Epicycloid: Also known as

An epicycle of an epicycloid is also known as a rotor.

The term has been taken by $\mathsf{Pr} \infty \mathsf{fWiki}$ from the children's toy Spirograph, which itself was taken from the term rotor as applied to the moving (rotating) part of a rotary machine.