white matter

noun

: neural tissue especially of the brain and spinal cord that consists largely of myelinated nerve fibers bundled into tracts, has a whitish color, and typically underlies the cortical gray matter

Examples of white matter in a Sentence

Recent Examples on the Web

Two other key areas — white matter, which contains connective fibers and delivers nerve signals, and the hippocampus, which processes memory – have also grown between 5.7% to 7.7%. —Lisa M. Krieger, The Mercury News, 3 May 2024

The increase in white matter suggests that brain cells are more interconnected, DeCarli said. —Lisa M. Krieger, The Mercury News, 3 May 2024

This neuroinflammation has been associated with changes in cerebral gray and white matter tissue. —Lauryn Higgins, Health, 16 Apr. 2024

Learning a new skill can impact a person’s white matter—the bundles of nerve fibers that connect different parts of the brain and help with focusing and learning function. —Didi Gluck, Vogue, 7 Dec. 2023

Word History

First Known Use

1674, in the meaning defined above

Kids Definition

white matter

noun

: whitish nerve tissue especially of the brain and spinal cord that consists largely of nerve fibers enclosed in a fatty material and that lies under the gray matter

Medical Definition

white matter

noun

: neural tissue especially of the brain and spinal cord that consists largely of myelinated nerve fibers bundled into tracts, has a whitish color, and typically underlies the gray matter