What do a.m. and p.m. stand for?


[kahr-dee-oid] /ˈkɑr diˌɔɪd/
noun, Mathematics
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
1745-55; < Greek kardioeidḗs heart-shaped. See cardi-, -oid Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
Cite This Source
Examples from the web for cardioid
  • It is preferable to use a cardioid condenser rather than a paraboloid condenser for darkfield fluorescent microscopy.
  • The microphones are typically cardioid or super cardioid microphones and therefore the best quality signal for each speaker.
  • Slightly higher power levels may be allowed in certain cases when cardioid antennas are utilized.
  • The cardioid, for instance, features a partially closed backside.
  • cardioid subwoofer prediction software examples with charts and photos.
British Dictionary definitions for 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
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
cardioid in Science
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 © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source

Word of the Day

Difficulty index for cardioid

Few English speakers likely know this word

Word Value for cardioid

Scrabble Words With Friends