Tradesperson is more obscene we hear (6)
I believe the answer is:
grocer
'tradesperson' is the definition.
'more obscene we hear' is the wordplay.
'more obscene' becomes 'grosser'.
'we hear' indicates a 'sounds like' (homophone) clue.
'grosser' is a homophone of 'GROCER'.
'is' is the link.
(Other definitions for grocer that I've seen before include "Food supplier" , "Food shop" , "Provision merchant" , "Seller of household items and food" , "Retail merchant" .)