Epicycle

Epicycle, an expression used in the Ptolemaic (q.v.) system of astronomy; the old belief that the celestial bodies moved in perfect circles round the earth was found to be inadequate to explain the varying position of the planets, a difficulty which led Ptolemy to invent his theory of epicycles, which was to the effect that each planet revolved round a centre of its own, greater or less, but that all these centres themselves moved in procession round the earth, a theory which fell to pieces before the investigations of Kepler and Newton.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Epicurus * Epidaurus
Eph`ori
Ephraem Syrus
Ephraim
Epic
Epic melody
Epicharis
Epicharmus
Epictetus
Epicureans
Epicurus
Epicycle
Epidaurus
Epidemic
Epigoni
Epigram
Epilepsy
Epimenides
Epimetheus
Epinal
Epinay, Madame d'
Epiphanius, St.