This allowed pub customers to get stuff off their chest (8)
I believe the answer is:
spittoon
'chest' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'this allowed pub customers to get stuff off their' is the wordplay.
I cannot really see how this works, but
'to' is found in the answer.
This may be the basis of clue (or it may be nonsense).
(Other definitions for spittoon that I've seen before include "One to aim at" , "old-fashioned receptacle" , "Old vessel for expectoration" , "I may collect rejected wine" , "Cuspidor" .)