1
: an act or process of forming fibers or fibrils
2
a
: a muscular twitching involving individual muscle fibers acting without coordination
b
: very rapid irregular contractions of the muscle fibers of the heart resulting in a lack of synchronism between heartbeat and pulse

Examples of fibrillation in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Some risks associated with stroke are hypertension (high blood pressure), atrial fibrillation (an irregular heartbeat) and smoking, according to the US Centers for Disease Control and Prevention. Gina Park, CNN, 20 Nov. 2024 Some of the potential adverse reactions have included renal dysfunction, lower leg compartment syndrome, rhabdomyolysis, liver injury, atrial fibrillation, and hepatitis. Sherri Gordon, Health, 26 Oct. 2024 Heart disease was defined as narrowed arteries, atrial fibrillation, stroke and heart failure. Nicole Villalpando, Austin American-Statesman, 21 Oct. 2024 Atrial fibrillation, or afib, an irregular and often rapid heartbeat, is associated with a 39 percent greater risk of problems with memory or cognition, the statement notes. Lisa Rapaport, EverydayHealth.com, 11 Oct. 2024 See all Example Sentences for fibrillation 

Word History

First Known Use

1845, in the meaning defined at sense 1

Time Traveler
The first known use of fibrillation was in 1845

Dictionary Entries Near fibrillation

Cite this Entry

“Fibrillation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fibrillation. Accessed 1 Jan. 2025.

Medical Definition

1
: an act or process of forming fibers or fibrils
2
a
: a muscular twitching involving individual muscle fibers acting without coordination
b
: very rapid irregular contractions of the muscle fibers of the heart resulting in a lack of synchronism between heartbeat and pulse see atrial fibrillation, ventricular fibrillation

More from Merriam-Webster on fibrillation

Last Updated: - Updated example sentences
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