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Epicycle - Meaning, Definition & English Examples

An epicycle is a small circle whose center moves along the circumference of a larger circle. It was used in ancient astronomy to explain the irregular motions of planets.

epicycle

/ˈɛpəˌsaɪkəl/ /ˈɛpɪˌsaɪkəl/

Definition:

A small circle whose center moves around the circumference of a larger one, used in astronomy.

Synonyms:

orbit, circle, revolution, cycle

Part of Speech:

noun

Antonyms:

straight line, linear motion

Common Collocations:

planetary motion, celestial mechanics, Ptolemaic system

Derivatives:

epicyclic, epicyclical

Usage Tips:

Use "epicycle" to describe secondary orbits in historical astronomy or metaphorically for complex processes.

Common Phrases:

wheels within wheels, cycle of cycles

Etymology:

From Greek "epi-" (upon) + "kyklos" (circle), referring to a circle moving on another circle.

Examples:

  • 1. The ancient Greeks used epicycles to explain planetary motion.
  • 2. Ptolemy's model included epicycles to account for retrograde motion.
  • 3. An epicycle is a smaller circle rolling around a larger one.
  • 4. Modern astronomy replaced epicycles with elliptical orbits.

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