epicycle
epicycle
Definition
epi·cy·cle (ep′ə sī′kəl)
noun
- a circle whose center moves along the circumference of another, larger circle: term used to describe planetary motions in the Ptolemaic system
- Geom. a circle which generates a hypocycloid or epicycloid by rolling around the circumference of a fixed circle
Etymology: ME epicicle < LL epicyclus < Gr epikyklos < epi-, upon + kyklos, a circle: see cycle
ep′i·cy′·clic (-sīk′lik) adjective or ep′i·cy′·cli·cal
epicycle
Usage Examples
Converse of object
- use: One such feature was epicycles used to explain the apparent backward motion of planets across the sky.
Modifies a noun
- theory: In the epicycle theory the Earth is in the center of a circle which has smaller circles rotating round its circumference.
Browse dictionary entries near epicycle
- Epicurus
- epicurism
- Epicureanism
- Epicurean
- epicure
- Epictetus
- epicritic
- epicranium
- epicotyl
- epicenter
