Arachnoid

1. n. One of the Arachnoidea.
2. a. Resembling a spider’s web; cobweblike.
3. a. Pertaining to a thin membrane of the brain and spinal cord, between the dura mater and pia mater.
4. a. Covered with, or composed of, soft, loose hairs or fibers, so as to resemble a cobweb; cobwebby.
5. n. The arachnoid membrane.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.