fibrillation

noun

fi·​bril·​la·​tion ˌfi-brə-ˈlā-shən How to pronounce fibrillation (audio)
ˌfī-
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

Example Sentences

Recent Examples on the Web In 2019, for instance, a study published in the Journal of the American Heart Association found that former N.F.L. players were far more likely to have atrial fibrillation than people in the general population. Alan Blinder, New York Times, 3 Jan. 2023 In November of 2021, the company presented their research at the American Heart Association’s Scientific Sessions 2021 and announced that their new algorithm accurately detected irregular heart rhythms and undiagnosed atrial fibrillation 98% of time. Christa Sgobba, SELF, 14 Apr. 2022 Individuals with atrial fibrillation should see a cardiologist to monitor their condition and often need anticoagulants to reduce their risk of stroke. Nick Blackmer, Verywell Health, 3 May 2023 Jansen had issues with atrial fibrillation in 2011, 2012, 2018, and 2022. Peter Abraham, BostonGlobe.com, 25 Mar. 2023 Many Alzheimer’s patients with CAA also suffer from other ailments, such as atrial fibrillation, that are normally treated with blood thinners, says Matthew Schrag, a Vanderbilt University physician and neuroscientist who specializes in CAA and assessed the report on the woman’s death for Science. Bycharles Piller, science.org, 27 Nov. 2022 Everybody with atrial fibrillation should have an evaluation as to the cause behind it (abnormal thyroid levels are a very common cause), but often a cause is never found. Dr. Keith Roach, oregonlive, 7 Sep. 2022 This is an area of controversy among sports cardiologists, some of whom argue that years of intense aerobic exercise can raise this risk of cardiac issues, most notably a problem called atrial fibrillation, where the upper chamber of the heart beats ineffectively. Peter Vigneron, Outside Online, 5 Jan. 2023 Cardiac arrest meanwhile can be caused by several conditions, including ventricular fibrillation, a type of arrhythmia where the lower chambers of the heart don't beat normally; coronary artery disease; heart failure; congenital heart disease; and commotio cordis, experts said. Mary Kekatos, ABC News, 3 Jan. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'fibrillation.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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 6 Jun. 2023.

Medical Definition

fibrillation

noun
fi·​bril·​la·​tion ˌfib-rə-ˈlā-shən How to pronounce fibrillation (audio) ˌfīb- How to pronounce fibrillation (audio)
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

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