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Glite Dictionary
epicycloid

epicycloid

1 9.9
A curve made by a point on a small circle rolling around a larger fixed circle
  • noun
  • /ˌɛpɪˈsaɪkloɪd/
  • Specialized
: epicicloide
  • The mathematical shape known as an epicycloid is formed when a circle rolls around the outside of another circle.

Examples

  • In geometry, an epicycloid can be visualized by tracing a point on the edge of a circle as it rolls along a larger circle.

  • The epicycloid curve is often used in mechanical engineering to design gear profiles.

  • Find a formula for the slope of the tangent to the "epicycloid" whose parametric equations are and.

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Surface Forms

epicycloid singular
epicycloids plural

Morphology

epicycloid = cycloid (semi-transparent) = epi + cyclo + oid

Formed by prefixing 'epi-' to 'cycloid' (a specific mathematical curve); the morphological process is regular but understanding requires knowledge of the technical base 'cycloid'.

Etymology

The word epicycloid comes from Greek parts epi- meaning 'upon', cyclo meaning 'circle', and -oid meaning 'like'. So an epicycloid is the 'circle-on' or 'circle-like' path made when a small circle rolls around the outside of a larger circle.