arrhythmia

American

[uh-rith-mee-uh, ey-rith-] / əˈrɪð mi ə, eɪˈrɪð- /

noun

Pathology.

any disturbance in the rhythm of the heartbeat.

arrhythmia British

/ əˈrɪðmɪə /

noun

any variation from the normal rhythm in the heartbeat

"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

arrhythmia Scientific

/ ə-rĭth′mē-ə /

An abnormal rhythm of the heart, often detectable on an electrocardiogram. Electrical impulses in the heart normally originate in the sinoatrial node of the right atrium during diastole and are transmitted through the atrioventricular node to the ventricles, causing the muscle contraction that usually occurs during systole. However, abnormalities of electrical conduction during diastole or systole can result in various alterations of the heartbeat, such as changes in heart rate, skipped or irregular beats, and fibrillation of the heart muscle, which can be life threatening. These electrical disturbances can be caused by metabolic abnormalities, inadequate blood supply (as in coronary artery disease), drug effects, chronic disease, and other factors. Arrhythmias are sometimes treated with the implantation of a pacemaker.

Other Word Forms

Etymology

Origin of arrhythmia

1885–90; < New Latin < Greek arrhythmía. See a- ⁶, rhythm, -ia

Compare meaning

How does arrhythmia compare to similar and commonly confused words? Explore the most common comparisons:

arrhythmia vs. dysrhythmia

Vocabulary lists containing arrhythmia

"Once Upon a Time," Vocabulary from the short story

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

And in 1987, a heart arrhythmia caused Soviet cosmonaut Aleksandr Laveykin to leave the Mir space station early.

From BBC • Jan. 14, 2026

Lang beguiled with common chords that no longer sounded common, with standard rhythms that intertwined, went on and off the beat, creating arrhythmia delight.

From Los Angeles Times • Nov. 19, 2025

We were interested in how these immune cells may promote arrhythmia.

From Science Daily • Oct. 13, 2025

When we removed this protein from neutrophils in mice, the arrhythmia burden after MI was reduced 12-fold.

From Science Daily • Oct. 13, 2025

I don’t know what an arrhythmia is, and I can’t bring myself to ask.

From "I Can Make This Promise" by Christine Day

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023