Complaint from the bar (7)
I believe the answer is:
railing
I believe this is a double definition.
'complaint' is the first definition.
(to rail can mean to complain)
'the bar' is the second definition.
'from' acts as a link.
(Other definitions for railing that I've seen before include "Fence of metal bars" , "Complaining - fence" , "Noisily protesting" , "Using abusive language" , "Protesting (about); fence" .)