white matter

American  

noun

Anatomy.

1. nerve tissue, especially of the brain and spinal cord, which primarily contains myelinated fibers and is nearly white in color.

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white matter British  

noun

1. Technical name: substantia alba.  the whitish tissue of the brain and spinal cord, consisting mainly of myelinated nerve fibres Compare grey matter

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white matter Scientific  

1. The whitish tissue of the vertebrate brain and spinal cord, made up chiefly of nerve fibers (axons) covered in myelin sheaths.

2. Compare gray matter

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Etymology

Origin of white matter

First recorded in 1830–40

Compare meaning

How does white-matter compare to similar and commonly confused words? Explore the most common comparisons:

• gray matter vs. white matter

Example Sentences

See Examples For:

white matter

In this new study, researchers noticed that participants scanned within 16 months of infection showed higher levels of inflammatory activity in white matter than those who had been sick for a longer period.

From Science Daily ● May 28, 2026

Participants with lower active B12 had a higher volume of white matter lesions, which are areas of brain injury that have been linked to cognitive decline, dementia, and stroke risk.

From Science Daily ● May 22, 2026

Even in this relatively healthy group, lower levels of active B12 were linked to slower thinking, slower visual processing, and more visible injury in the brain's white matter.

From Science Daily ● May 22, 2026

The research team is now exploring whether mitochondrial damage extends beyond Purkinje cells to other cerebellar cell types, including oligodendrocytes, which help form white matter, and astrocytes, which support overall brain function.

From Science Daily ● Jan. 6, 2026

In Nucula the lateral ganglia are larger in proportion and the distribution of the gray and white matter is more irregular.

From Journal of Entomology and Zoology Volume 11, Number 4, December 1919 by Alexander, Charles P.