fi·​bril | \ ˈfī-brəl How to pronounce fibril (audio) , ˈfi- How to pronounce fibril (audio) \

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

Other Words from fibril

fibrillar \ ˈfi-​brə-​lər How to pronounce fibril (audio) , ˈfī-​ \ adjective

Examples of fibril in a Sentence

Recent Examples on the Web Finally, there is convincing evidence that the most readily detectable form of amyloid, known as a fibril, is not the worst type. Sam Gandy, STAT, 17 June 2021 Some researchers thought the mineral was mostly contained inside fibrils; others believed the mineral cladded the protein like armor. Angus Chen, Scientific American, 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,, 19 Feb. 2018 Perhaps the fibrils could help women eliminate bad sperm. Giorgia Guglielmi, Science | AAAS, 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.

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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Dictionary Entries Near fibril



fibrillar theory

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Cite this Entry

“Fibril.” Dictionary, Merriam-Webster, Accessed 26 May. 2022.

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More Definitions for fibril


fi·​bril | \ ˈfīb-rəl How to pronounce fibril (audio) , ˈfib- How to pronounce fibril (audio) \

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


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