gray matter

noun

1. Anatomy.,  nerve tissue, especially of the brain and spinal cord, that contains fibers and nerve cell bodies and is dark reddish-gray.

2. Informal.,  brains or intellect.

gray matter

1. The brownish-gray tissue of the vertebrate brain and spinal cord, made up chiefly of the cell bodies and dendrites of neurons.

2. Compare white matter

Word History and Origins

Origin of gray matter¹

First recorded in 1830–40

Idioms and Phrases

Brains, intellect, as in If you'd only use your gray matter, you'd see the answer in a minute. This expression refers to actual brain tissue that is gray in color. Agatha Christie's fictional detective, Hercule Poirot, constantly alludes to using the little gray cells for solving a crime. [Late 1800s]

Example Sentences

Interestingly, some findings suggest that gray matter volume may partially recover after menopause, hinting at the brain's ability to adapt through neuroplasticity.

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Frankly, the film has so little on its mind in general that if a butcher’s cleaver slammed through its skull, it would strike cotton candy instead of gray matter.

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Neuroscientists typically ascribe consciousness and abstract thought to the cerebral cortex, which evolved later in human evolution and wraps around the brain's outer layer in folded gray matter.

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The results showed that lower pulmonary gas exchange may be associated with cognitive dysfunction, as well as lower gray matter and white matter volumes in patients with long COVID.

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AFM attacks motor neurons in the spinal cord’s gray matter, which controls movement.

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