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 had reduced frontal and occipital lobe volume and more damage in the brain's white matter, changes that have been associated with aging, stroke risk, 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

Surrounding that is white matter, made up of astrocytes and long nerve fibers that carry signals between the brain and the rest of the body.

From Science Daily ● Feb. 13, 2026

"Our work highlights a fundamental link between the brain's white matter connectivity and its local computational properties," Parkes said.

From Science Daily ● Jan. 3, 2026

The white matter called pus in a sore is largely made of white blood cells which came there to fight the germs and were killed in the battle.

From Health Lessons Book 1 by Davison, Alvin