epi·​cy·​cle | \ ˈe-pə-ˌsī-kəl How to pronounce epicycle (audio) \

Definition of epicycle

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

Other Words from epicycle

epicyclic \ ˌe-​pə-​ˈsī-​klik How to pronounce epicycle (audio) , -​ˈsi-​klik \ adjective

Examples of epicycle in a Sentence

Recent Examples on the Web In order to reconcile circular orbits with actual planetary behavior, Copernicus continued the tradition, developed by Ptolemy, of arguing that planets spin on wheels, known as epicycles. National Geographic, 9 Apr. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'epicycle.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of epicycle

14th century, in the meaning defined at sense 1

History and Etymology for epicycle

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

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The first known use of epicycle was in the 14th century

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Dictionary Entries Near epicycle



epicyclic train

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Cite this Entry

“Epicycle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/epicycle. Accessed 16 Aug. 2022.

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More from Merriam-Webster on epicycle

Britannica.com: Encyclopedia article about epicycle


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