pia mater
noun
pia ma·ter
ˈpī-ə-ˌmā-tər 
ˈpē-ə-ˌmä-
ˈpē-ə-ˌmä-
: the thin vascular membrane that invests the brain and spinal cord internal to the arachnoid and dura mater
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Her doctors noted in their report that the worms typically stay in the pia mater of the brain, a delicate innermost layer of tissue that surrounds the brain and spinal cord.
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Ars Technica, 11 Mar. 2025
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Ars Technica, 11 Mar. 2025
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“Pia mater.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pia%20mater. Accessed 30 Oct. 2025.
Copy CitationMedical Definition
pia mater
noun
pia ma·ter
-ˈmāt-ər
: the delicate and highly vascular membrane of connective tissue investing the brain and spinal cord, lying internal to the arachnoid and dura mater, dipping down between the convolutions of the brain, and sending an ingrowth into the anterior fissure of the spinal cord
called also pia
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