From HomoExcelsior

1. Of or relating to a delicate membrane enclosing the spinal cord and brain. 2. Of, relating to, or resembling arachnids. 3. Covered with or consisting of thin, soft, entangled hairs or fibers resembling those of a cobweb or spider's web. 4. A delicate membrane that encloses the spinal cord and brain, and lies between the pia mater and dura mater.

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