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From dictionary.com:

From dictionary.com:
hy?po?cy?cloid
? ?/?ha?p??sa?kl??d/ Show Spelled Pronunciation [hahy-puh-sahy-kloid] Show IPA Pronunciation
–noun Geometry.
a curve generated by the motion of a point on the circumference of a circle that rolls internally, without slipping, on a given circle.
? ?/?ha?p??sa?kl??d/ Show Spelled Pronunciation [hahy-puh-sahy-kloid] Show IPA Pronunciation
–noun Geometry.
a curve generated by the motion of a point on the circumference of a circle that rolls internally, without slipping, on a given circle.

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