fasciculus

noun

fas·​cic·​u·​lus fə-ˈsi-kyə-ləs How to pronounce fasciculus (audio)
fa-
plural fasciculi fə-ˈsi-kyə-ˌlī How to pronounce fasciculus (audio)
fa-
1
: a slender bundle of anatomical fibers (such as nerve fibers) : fascicle sense 1b
2
: one of the divisions of a book published in parts : fascicle sense 2

Examples of fasciculus 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.
Our mental calendar involves circuits in the left angular gyrus, important for sequence discrimination and connected to the same hippocampal place cell or grid cell via a band of fibers: the inferior longitudinal fasciculus. Scientific American, 1 June 2020 This view shows the three major tracts involved with language and literacy skills: the arcuate fasciculus, shaded in white, which connects brain areas involved with receptive and expressive language. Sandee Lamotte, CNN, 4 Nov. 2019 Connecting Broca’s area with Wernicke’s is a neural network: a thick, curving bundle of billions of nerve fibres, the arcuate fasciculus, which integrates the production and the comprehension of language. Rachel Aviv, The New Yorker, 25 May 2018 The vertical occipital fasciculus, or VOF, is identified in a postmortem human brain in 1909, but labeled with a different name. Jenny Blair, Discover Magazine, 1 Oct. 2015

Word History

Etymology

New Latin, from Latin

First Known Use

1713, in the meaning defined at sense 1

Time Traveler
The first known use of fasciculus was in 1713

Browse Nearby Words

Cite this Entry

“Fasciculus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fasciculus. Accessed 9 Sep. 2025.

Medical Definition

fasciculus

noun
fas·​cic·​u·​lus fə-ˈsik-yə-ləs, fa- How to pronounce fasciculus (audio)
plural fasciculi -ˌlī How to pronounce fasciculus (audio)
: a slender bundle of anatomical fibers:
a
: a bundle of skeletal muscle cells surrounded by perimysium and forming one of the constituent elements of a muscle
b
: a bundle of nerve fibers surrounded by perineurium
specifically : a bundle of nerve fibers having a common origin, termination, and function : tract sense 2
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