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

They also showed greater volumes of white matter hyperintensities, which are signs of cerebral small blood vessel disease and have been linked to cognitive decline and dementia.

From Science Daily ● Jul. 21, 2026

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

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

"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

A transverse section of the cord reveals that it is composed of white matter externally and of gray matter internally.

From Special Report on Diseases of the Horse by Michener, Charles B.