cardioid

noun

car·​di·​oid ˈkär-dē-ˌȯid 

: 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

• 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

The Sennheiser e835 also features a cardioid pickup pattern, which is good at isolating the user’s voice, especially in spaces or venues with poor acoustics. —Mark Sparrow, Forbes.com, 31 Aug. 2025

All the capsules on stage are set to super cardioid with low-cut and the 12db pad engaged. —Mark Sparrow, Forbes, 22 Dec. 2024

This was coupled with a doughnut shape of 68 triple 21-inch cardioid subs around the stage for even coverage throughout the venue, backed up by additional subs for the points furthest away. —Jeff Ihaza, Rolling Stone, 2 July 2024

Points in the main cardioid correspond to functions that, when iterated from a starting value of zero, converge to a single number. —Quanta Magazine, 26 Jan. 2024

The mic also comes with four different polar pattern options: cardioid, omnidirectional, stereo, and bidirectional. —Tom Price, Popular Mechanics, 14 Mar. 2023

The cells stay behind on the cardioid, which then starts to recover. —Theresa MacHemer, Smithsonian Magazine, 20 May 2021

Word History

First Known Use

1747, in the meaning defined above

Rhymes for cardioid

• adenoid
• alkaloid
• amoeboid
• amyloid
• aneroid
• anthropoid
• arachnoid
• asteroid
• benzenoid
• carcinoid
• celluloid
• coronoid