Carpet surface (3)
I believe the answer is:
nap
'carpet surface' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for nap that I've seen before include "Card game - quick sleep" , "Siesta" , "Sleep - card game - fibres on a snooker table" , "Raised fibres on surface of cloth or leather" , "A brief informal sleep" .)