Definition of "grey matter" []

• Brains; a person's ability to think. (noun)
• A collection of cell bodies and (usually) dendritic connections, in contrast to white matter. (noun)

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• "A broad layer of nerve-containing grey matter found bilaterally throughout the mesencephalon, or upper brain stem."
• "The whorls of grey matter swelled to entrails, they curled round one another like muscular snakes, became vague and misty like the spiral nebulae on astronomical charts ..."