Thick rug type (4)
I believe the answer is:
shag
'thick rug type' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for shag that I've seen before include "flighty creature" , "Kind of cormorant - tobacco" , "As water bird" , "Green cormorant" , "Coarse tobacco - cormorant" .)