Siesta (3)
I believe the answer is:
nap
'siesta' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for nap that I've seen before include "A short sleep or snooze" , "Pile of material" , "Sleep - card game - fibres on a snooker table" , "Raised fibres on surface of cloth or leather" , "one akin to whist" .)