Epicycle

model of planetary motion in which planets moved in a small circle which in turn moves around the Earth

epicycle. noun. epi·​cy·​cle ˈep-ə-ˌsī-kəl. : a circle according to an early astronomy theory in which a planet moves and which has a center that is itself carried around at the same time on the circumference of a larger circle.[1]

References

change
  1. Merriam-Webster