pia mater


: the thin vascular membrane that invests the brain and spinal cord internal to the arachnoid and dura mater

Word History


Middle English, from Medieval Latin, from Latin, tender mother

First Known Use

14th century, in the meaning defined above

Time Traveler
The first known use of pia mater was in the 14th century

Dictionary Entries Near pia mater

Cite this Entry

“Pia mater.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pia%20mater. Accessed 18 Jul. 2024.

Medical Definition

pia mater

pia ma·​ter -ˈmāt-ər How to pronounce pia mater (audio)
: 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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