a. [ Gr. &unr_; like a cobweb; &unr_; spider, spider's web + e'i^dos form. ] 1. Resembling a spider's web; cobweblike. [ 1913 Webster ]
2. (Anat.) Pertaining to a thin membrane of the brain and spinal cord, between the dura mater and pia mater. [ 1913 Webster ]
3. (Bot.) Covered with, or composed of, soft, loose hairs or fibers, so as to resemble a cobweb; cobwebby. [ 1913 Webster ]
n. 1. (Anat.) The arachnoid membrane. [ 1913 Webster ]
2. (Zool.) One of the Arachnoidea. [ 1913 Webster ]
a. (Anat.) Pertaining to the arachnoid membrane; arachnoid. [ 1913 Webster ]
‖n. pl. [ NL. ] (Zool.) Same as Arachnida. [ 1913 Webster ]