Cat coat (3)
I believe the answer is:
fur
'cat coat' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for fur that I've seen before include "Animal's coat converted to human use" , "Coating formed on tongue of sick person" , "Eg, sable or ermine" , "Eg, sable or mink" , "Hard water pipe coating" .)