Definitions
from The American Heritage® Dictionary of the English Language, 4th Edition
 n. The curve described by a point on the circumference of a circle as the circle rolls on the outside of the circumference of a second, fixed circle.
from Wiktionary, Creative Commons Attribution/ShareAlike License
 n. The locus of a point on the circumference of a circle that rolls without slipping on the circumference of another circle.
from the GNU version of the Collaborative International Dictionary of English
 n. A curve traced by a point in the circumference of a circle which rolls on the convex side of a fixed circle.
from The Century Dictionary and Cyclopedia
 n. In geometry, a curve generated by the motion of a point on the circumference of a circle which rolls upon the convex side of a fixed circle. These curves were invented by the Danish astronomer Roemer in 1674.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
 n. a line generated by a point on a circle rolling around another circle
Etymologies
Sorry, no etymologies found.
Examples

Ciclo, above, a modern update to the velocipedestyle bicycle that used a hubless "epicycloid" transmission system.

Alien eggplants, they deign epicycloid arcs aimlessly spaced on a fragmented landscape of trap stone and tar, terra cotta chimney caps and aluminum antennae.

Cycloid External epicycloid, described by a circle rolling about a fixed circle inside of it.

External epicycloid, described by a circle rolling about a fixed circle inside of it.

With the aid of a system of tangents of which I first showed him the rule and the method of construction, my artist has obtained the ordinary cycloid, followed by the interior and the exterior epicycloid and, lastly, the same curves both lengthened and shortened.
The Life of the fly; with which are interspersed some chapters of autobiography

Luca Schieppati's velocipedal epicycloid stationary bike is a mouthful and an eyeful

A curve described in space by a point of a circle or sphere, which itself is carried along at the same time, is some kind of cycloid; if the centre of the tracing circle travels along a straight line, we get the ordinary cycloid, the curve traced in air by a nail on a coachwheel; but if the centre of the tracing circle be carried round another circle the curve described is called an epicycloid.

You know the ordinary nephroid as the reflected catacaustic of a circle, the involute of Caley’s sextic, and a generally goodnatured twocusped epicycloid.
Rambles at starchamber.com » Blog Archive » Imaginary Law Firms, Part 1: Brannock, Foley, and Freeth
Comments
Log in or sign up to get involved in the conversation. It's quick and easy.