Main Entry: epi·cy·cle

Pronunciation: \ˈe-pə-ˌsī-kəl\

Function: noun

Etymology: Middle English epicicle, from Late Latin epicyclus, from Greek epikyklos, from epi- + kyklos circle — more at wheel

Date: 14th century

1 in Ptolemaic astronomy : a circle 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
2 : a process going on within a larger one

— epi·cy·clic \ˌe-pə-ˈsī-klik, -ˈsi-klik\ adjective