Answer: arachnoid

AnswerCrossword Clue
ARACHNOIDSpiderlike
ARACHNOIDDaddy longlegs, e.g.
arachnoidlike a cobweb / the arachnoid membrane, a fine delicate membrane which is the middle of the three meninges enveloping the brain and spinal cord
arachnoidof or relating to a thin membrane of the brain and spinal cord that lies between the dura mater and the pia mater