cardioid

American  

[kahr-dee-oid] / ˈkɑr diˌɔɪd /

noun

Mathematics.

1. 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).

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cardioid British  

/ ˈkɑːdɪˌɔɪd /

noun

1. 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

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cardioid Scientific  

/ kär′dē-oid′ /

1. 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.

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Etymology

Origin of cardioid

First recorded in 1745–55, cardioid is from the Greek word kardioeidḗs heart-shaped. See cardi-, -oid

Example Sentences

See Examples For:

cardioid

Image: Razer Compared to the other two models, the Pro’s detachable microphone is a “supercardioid” type instead of the standard cardioid mic.

From The Verge ● Oct. 21, 2021

Electro-Voice RE27N/D $499 Pro-level broadcasting dynamic cardioid multipurpose microphone.

From The Verge ● Sep. 2, 2021

What I’ve been recommending to guests lately is Audio-Technica’s ATR2100x-USB cardioid dynamic USB/XLR microphone.

From The Verge ● Sep. 2, 2021

In Example 7.17 we found the area inside the circle and outside the cardioid by first finding their intersection points.

From Textbooks ● Mar. 30, 2016

When c = a or = ∞ the curve reduces to the cardioid or the two cusped epicycloid previously discussed.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 5 "Cat" to "Celt" by Various