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
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.
Maillard has made a name for herself by mapping the brain’s white matter, the silent highways that carry thoughts and impulses through the mind. Cathie Anderson, Sacbee.com, 21 Apr. 2025 Researchers also evaluated white matter in the brain using an MRI technique called diffusion tensor imaging (DTI), which measures the movement of water molecules in the brain. Tom Gavin, EverydayHealth.com, 24 Mar. 2025 Healthy Eating and Slimmer Waists Tied to Better Brain Health Jensen and her team found that higher diet quality in midlife and into older age was associated with better structural and functional connectivity of the hippocampus and better white matter integrity. Tom Gavin, EverydayHealth.com, 24 Mar. 2025 Mechanisms of white matter change induced by meditation training PubMed. Avery Hurt, Discover Magazine, 17 Mar. 2025 See All Example Sentences for white matter

Word History

First Known Use

1674, in the meaning defined above

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

Browse Nearby Words

Cite this Entry

“White matter.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/white%20matter. Accessed 1 May. 2025.

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

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!