the middle of three membranous layers (meninges) that cover and protect the surface of the brain and spinal cord. The name is derived because the strands of tissue resemble spiders' webs. Also known as arachnoid- arachnoid membrane.

ARACHNOID MATER: "The arachnoid mater is the middle of three layers that cover the overall surface of the brain."
Cite this page: N., Pam M.S., "ARACHNOID MATER," in, April 7, 2013, (accessed May 11, 2021).