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atrial fibrillation

American  
[ey-tree-uhl fib-ruh-ley-shuhn] / ˈeɪ tri əl ˌfɪb rəˈleɪ ʃən /

noun

Pathology.
  1. a cardiac arrhythmia, or irregular heartbeat, caused by rapid, chaotic electrical impulses to the atria. AF, AFib.


Etymology

Origin of atrial fibrillation

First recorded in 1905–10

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.

See Examples For:

Caffeine also blocks a substance that can cause atrial fibrillation, an arrhythmia that can lead to strokes.

From The Wall Street Journal Jul. 20, 2026

According to Civello, the next wave — in which wearables can detect conditions like atrial fibrillation, hypertension and sleep apnea — is happening now.

From MarketWatch May 28, 2026

It’s a common alternative for patients with atrial fibrillation who can’t take long-term blood thinners.

From Barron's May 27, 2026

Women experiencing heart attacks, heart failure, atrial fibrillation or stroke require timely and high quality treatment.

From Science Daily Feb. 27, 2026

For example, portfolio company Laminar, which developed a treatment for certain patients with the heart-rhythm disorder atrial fibrillation, was acquired by Johnson & Johnson in 2023, a down year for M&A, he said.

From The Wall Street Journal Feb. 12, 2026

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