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epicycloid

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noun epi·cy·cloid \ˌe-pə-ˈsī-ˌklȯid\

Definition of epicycloid

  1. :  a curve traced by a point on a circle that rolls on the outside of a fixed circle

epicycloidal

play \ˌe-pə-sī-ˈklȯi-dəl\ adjective

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Illustration of epicycloid

First Known Use of epicycloid

circa 1696

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