Sleeps around for a while (4)
I believe the answer is:
span
'a while' is the definition.
(thesaurus)
'sleeps around' is the wordplay.
'sleeps' becomes 'naps' (napping is a kind of sleeping).
'around' says the letters should be written in reverse.
'naps' in reverse letter order is 'SPAN'.
'for' acts as a link.
(Other definitions for span that I've seen before include "Cover" , "Extent - 9 inches" , "Extend from end to end, say bridge" , "Width of wings" , "Length of bridge - 9 inches!" .)