fi·​bril | \ˈfī-brəl, ˈfi- \

Definition of fibril 

: 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

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Other Words from fibril

fibrillar \ˈfi-​brə-​lər, ˈfī-​ \ adjective

Examples of fibril in a Sentence

Recent Examples on the Web

Some researchers thought the mineral was mostly contained inside fibrils; others believed the mineral cladded the protein like armor. Angus Chen, Scientific American, "Core Strength: Extreme “Close Ups” May Help Explain Why Our Bones Are So Strong," 3 May 2018 The image that is a dehydration and oxidation of the linen fibers goes only two to three fibrils into the cloth. Joanne Berger Dumound/special To,, "Local lecturer brings world class Shroud of Turin exhibit to Greater Cleveland," 19 Feb. 2018 Perhaps the fibrils could help women eliminate bad sperm. Giorgia Guglielmi, Science | AAAS, "Protein tangles behind Alzheimer’s disease may be critical for human reproduction," 11 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fibril.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of fibril

1664, in the meaning defined above

History and Etymology for fibril

New Latin fibrilla, diminutive of Latin fibra

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Time Traveler for fibril

The first known use of fibril was in 1664

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More Definitions for fibril


fi·​bril | \ˈfīb-rəl, ˈfib- \

Medical Definition of fibril 

: a small filament or fiber: as

a : one of the fine threads into which a striated muscle fiber can be longitudinally split

b : neurofibril

Comments on fibril

What made you want to look up fibril? Please tell us where you read or heard it (including the quote, if possible).


a soft lustrous wool fabric with mohair

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