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

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

Among participants with mild cognitive impairment, the connection between Alzheimer's related biochemicals and enlarged perivascular spaces was stronger than the connection with white matter damage.

From Science Daily ● Jan. 3, 2026

"The brain achieves this by leveraging its white matter connectivity to share information across regions, and this integration is crucial for human behavior."

From Science Daily ● Jan. 3, 2026

The researchers also looked at white matter damage, a widely used indicator of Alzheimer's, and found it was associated with six of the seven blood markers.

From Science Daily ● Jan. 3, 2026

It is composed of the same substances as the brain; but the arrangement is exactly reversed, the white matter encompassing or surrounding the gray matter instead of being encompassed by it.

From A Treatise on Physiology and Hygiene For Educational Institutions and General Readers by Hutchison, Joseph Chrisman