1. 
[syn: diaphanous, filmy, gauzy, gauze-like, gossamer, see-through, sheer, transparent, vaporous, vapourous, cobwebby]
2.  covered with cobwebs; 
The Collaborative International Dictionary of English v.0.48:
Cobwebby \Cob"web`by\, a.
   Abounding in cobwebs, or any fine web; resembling a cobweb.
   [1913 Webster]
WordNet (r) 3.0 (2006):
cobwebby
    adj 1: so thin as to transmit light; "a hat with a diaphanous
           veil"; "filmy wings of a moth"; "gauzy clouds of
           dandelion down"; "gossamer cobwebs"; "sheer silk
           stockings"; "transparent chiffon"; "vaporous silks" [syn:
           diaphanous, filmy, gauzy, gauze-like, gossamer,
           see-through, sheer, transparent, vaporous,
           vapourous, cobwebby]
    2: covered with cobwebs