white matter

noun

: neural tissue especially of the brain and spinal cord that consists largely of myelinated nerve fibers bundled into tracts, has a whitish color, and typically underlies the cortical gray matter

Examples of white matter in a Sentence

Recent Examples on the Web While grey matter decreases, there were significant increases in white matter, the nerve fibres that connect neurons and help different brain regions communicate. Chas Newkey-Burden, The Week Uk, theweek, 18 Sep. 2024 Diverse areas can be linked together by edges representing the brain’s structural connections: thick bundles of tubular wires called white matter tracts that tie together brain regions. Max Bertolero, Scientific American, 1 July 2019 This helped researchers to identify the brain’s six cortical layers and white matter. Isabel Fraser, WIRED, 15 Aug. 2024 Compared to people without depression or migraine, those with both had lower overall volume, decreased gray and white matter, and less cerebrospinal fluid.5 Serotonin: Both conditions feature low levels of serotonin. Mark Gurarie, Verywell Health, 14 Aug. 2024 See all Example Sentences for white matter 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'white matter.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1674, in the meaning defined above

Time Traveler
The first known use of white matter was in 1674

Dictionary Entries Near white matter

Cite this Entry

“White matter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/white%20matter. Accessed 3 Oct. 2024.

Kids Definition

white matter

noun
: whitish nerve tissue especially of the brain and spinal cord that consists largely of nerve fibers enclosed in a fatty material and that lies under the gray matter

Medical Definition

white matter

noun
: neural tissue especially of the brain and spinal cord that consists largely of myelinated nerve fibers bundled into tracts, has a whitish color, and typically underlies the gray matter

More from Merriam-Webster on white matter

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