Slimmer's bar (5)
I believe the answer is:
local
I believe this is a double definition.
'slimmer's' is the first definition.
(lo-cal, low in calories)
'bar' is the second definition.
(thesaurus)
(Other definitions for local that I've seen before include "Pub - not far away" , "Neighbourhood pub or resident" , "(Pub) of the district" , "Anaesthetic that numbs one area of the body" , "Stopping regularly" .)