Bar language (8)
I believe the answer is:
legalese
This could be a double definition.
'bar' is the first definition.
The definition and answer can be both related to communication as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'language' is the second definition.
(I have seen 'formal language' mean 'legalese' so perhaps 'language' could also mean 'legalese')
Can you help me to learn more?
(Other definitions for legalese that I've seen before include "barman's peculiar words" , "contract wording?" , "Solicitor's jargon" , "such language at the bar!" , "Special terms" .)