# cardioid

[kahr-dee-oid]

- a somewhat heart-shaped curve, being the path of a point on a circle that rolls externally, without slipping, on another equal circle. Equation: r = a(1−cosA).

## Origin of cardioid^{}

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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

# cardioid

- a heart-shaped curve generated by a fixed point on a circle as it rolls around another fixed circle of equal radius, a. Equation: r = a (1 – cos φ), where r is the radius vector and φ is the polar angle

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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# cardioid

[kär′dē-oid′]

- A heart-shaped plane curve, the locus of a fixed point on a circle that rolls on the circumference of another circle with the same radius.

The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.