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.

---

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

---

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

---

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

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

A recent major study assessed efficiency of brain networks, essentially how the brain is wired, through white matter topology.

From Science Daily ● Feb. 19, 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

The wound should begin to discharge white matter on the second day in hot weather or the third in cold, and from that time a good recovery may be expected.

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