fibril

noun

fi·​bril ˈfī-brəl How to pronounce fibril (audio) ˈfi- How to pronounce fibril (audio)
: a small filament or fiber: such as
a
: root hair
b(1)
: one of the fine threads into which a striated muscle fiber can be longitudinally split
(2)
: neurofibril
fibrillar
ˈfi-brə-lər How to pronounce fibril (audio) ˈfī- How to pronounce fibril (audio)
adjective

Examples of fibril 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.
The latter allow the nanoparticles to bind to and destroy harmful α-synuclein fibrils, while the former specifically target a temperature-sensitive receptor in dopamine-producing neurons that are in turn stimulated by the gold nanoshells, which translate the laser light into heat. — Yaakov Katz, Newsweek, 17 Jan. 2025 Similar processes might underlie the development of protein aggregates tied to other neurodegenerative disorders, such as the amyloid fibrils found in the brains of people with Alzheimer’s disease or the synuclein protein deposits implicated in Parkinson’s disease. — Trevor Grandpre, Scientific American, 14 Aug. 2024

Word History

Etymology

New Latin fibrilla, diminutive of Latin fibra

First Known Use

1664, in the meaning defined above

Time Traveler
The first known use of fibril was in 1664

Browse Nearby Words

fibre
fibril
fibrillar theory
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Cite this Entry

“Fibril.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fibril. Accessed 28 Mar. 2025.

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Medical Definition

fibril

noun
fi·​bril ˈfīb-rəl How to pronounce fibril (audio) ˈfib- How to pronounce fibril (audio)
: a small filament or fiber: as
a
: one of the fine threads into which a striated muscle fiber can be longitudinally split
b
: neurofibril
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