car·​di·​oid | \ˈkär-dē-ˌȯid \

Definition of cardioid 

: a heart-shaped curve that is traced by a point on the circumference of a circle rolling completely around an equal fixed circle and has an equation in one of the forms ρ = a(1 ± cos θ) or ρ = a(1 ± sin θ) in polar coordinates

Illustration of cardioid

Illustration of cardioid

cardioid: ABP fixed circle; PCD first position of rolling circle; P tracing point; PM diameter through P; P1, P2, P3, P4 various positions of P; P1M1, P2M2, P3M3, P4M4 various positions of PM

Examples of cardioid in a Sentence

Recent Examples on the Web

This compact cardioid condenser mic jacks into the phone via a Lightning dongle to bring your sparkling dialog into focus. Arielle Pardes, WIRED, "Gadgets to Help You Shoot Pro-Quality Movies on Your iPhone," 1 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cardioid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of cardioid

1753, in the meaning defined above

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The first known use of cardioid was in 1753

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