myofibril

noun

myo·​fi·​bril ˌmī-ə-ˈfī-brəl How to pronounce myofibril (audio) -ˈfi- How to pronounce myofibril (audio)
: any of the longitudinal parallel contractile elements of a muscle cell that are composed of myosin and actin
myofibrillar adjective

Examples of myofibril in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Sarcoplasmic and myofibril types are the two main categories under which this process falls. Amber Smith, Discover Magazine, 12 Oct. 2022 Our bodies rebuild these tears by adding either sarcomeres, which are fibrous proteins inside muscle cells, or myofibrils—chains of rod-like units also in muscle cells that give them their striped appearance. Popular Science, 1 Jan. 2019 More myofibrils will increase the mass of a muscle cell while more sarcomeres will increase the length. Popular Science, 1 Jan. 2019

Word History

Etymology

New Latin myofibrilla, from my- + fibrilla fibril

First Known Use

1898, in the meaning defined above

Time Traveler
The first known use of myofibril was in 1898

Dictionary Entries Near myofibril

Cite this Entry

“Myofibril.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/myofibril. Accessed 16 Nov. 2024.

Kids Definition

myofibril

noun
myo·​fi·​bril ˌmī-ō-ˈfīb-rəl How to pronounce myofibril (audio) -ˈfib- How to pronounce myofibril (audio)
: any of the long thin contracting protein subunits of a muscle cell that are composed of actin and myosin filaments

Medical Definition

myofibril

noun
myo·​fi·​bril ˌmī-ō-ˈfīb-rəl, -ˈfib- How to pronounce myofibril (audio)
: one of the longitudinal parallel contractile elements of a muscle cell that are composed of myosin and actin
myofibrillar adjective

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