gray matter


Definition of gray matter 

1 : neural tissue especially of the brain and spinal cord that contains nerve-cell bodies as well as nerve fibers and has a brownish-gray color

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Examples of gray matter in a Sentence

she's got the gray matter to figure that equation out

Recent Examples on the Web

In his imaging studies, school-aged Romanian orphans sent to live with foster families had brains with less gray matter than orphans sent to nurturing foster homes before age 2. Washington Post, "Science Says: How family separation may affect kids’ brains," 28 June 2018 The Hulk demo within the sprawling, 930-square-meter S.T.A.T.I.O.N. exhibit begins with an actual MRI scan of a human brain that represents Banner’s gray matter. Larry Greenemeier, Scientific American, "Marvel Comics Gets Inside the Heads of the Avengers," 21 Aug. 2014 Three nearly identical genes could help explain how 0.5 liters of gray matter in early human ancestors became the 1.4-liter organ that has made our species so successful and distinctive. Elizabeth Pennisi, Science | AAAS, "Trio of genes supercharged human brain evolution," 31 May 2018 Now in its fifth year, Mathzilla 5.0 pits students in grades 4 through 6 against one another in individual and group competitions designed to flex gray matter with a series of tasks centered on speed, accuracy and hand-eye coordination. Sara Cardine,, "LCUSD elementary students vie for top prize, bragging rights at Mathzilla 5.0 competition," 4 May 2018 The study found widespread reductions in the volume of gray matter in the brains of children with ADHD. Amy Ellis Nutt,, "Brain abnormalities found in 4- and 5-year-olds with ADHD, researchers say," 26 Mar. 2018 Some studies suggest that mindfulness meditation may increase gray matter density in the hippocampus, a brain region essential to memory. Bruce Lieberman, Washington Post, "Mindfulness meditation is huge, but science isn’t sure how, or whether, it works," 24 Mar. 2018 It was found that among those who drank alcohol, adults — and to a lesser extent, teens — had a reduction in gray matter volume. Josh Magness, sacbee, "Weed won't cause brain damage the way alcohol will, study finds," 14 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'gray matter.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of gray matter

1809, in the meaning defined at sense 1

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The first known use of gray matter was in 1809

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More Definitions for gray matter

gray matter


English Language Learners Definition of gray matter

: the tissue that makes up the brain

gray matter


Medical Definition of gray matter 

: neural tissue especially of the brain and spinal cord that contains cell bodies as well as nerve fibers, has a brownish gray color, and forms most of the cortex and nuclei of the brain, the columns of the spinal cord, and the bodies of ganglia

called also gray substance

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Comments on gray matter

What made you want to look up gray matter? Please tell us where you read or heard it (including the quote, if possible).


one that holds something together

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