| arachnoid membrane | |
noun | |
| the middle of the 3 meninges [syn: arachnoid] |
arachnoid membrane n.
A delicate fibrous membrane forming the middle of the three coverings of the brain and spinal cord, closely attached to the dura mater, from which it is separated only by the subdural cleft, but separated from the pia mater by the subarachnoid space.