Banter about posh street in Paris upset driver (9)
I believe the answer is:
chauffeur
'driver' is the definition.
(chauffeur is a kind of driver)
'banter about posh street in paris upset' is the wordplay.
'banter' becomes 'chaff' ('chaff' can be a synonym of 'banter').
'about' is an insertion indicator.
'posh' becomes 'u' (abbreviation for upper-class - opposite to non-u).
'street in paris' becomes 'rue'.
'upset' is a reversal indicator.
'rue' in reverse letter order is 'eur'.
'chaff' placed around 'u' is 'chauff'.
'chauff'+'eur'='CHAUFFEUR'
(Other definitions for chauffeur that I've seen before include "Driver for private car" , "Professional driver" , "One employed to drive a car for someone" , "Personal driver" , "One is paid to drive a car" .)