Passenger vehicle coming from market overturned (4)
I believe the answer is:
tram
'passenger vehicle' is the definition.
(type of public transport)
'market overturned' is the wordplay.
'market' becomes 'mart' (synonyms).
'overturned' shows that the letters should be reversed in order.
'mart' written backwards gives 'TRAM'.
'coming from' acts as a link.
(Other definitions for tram that I've seen before include "Streetcar" , "An early form of Luas in Dublin transport" , "It runs on rails" , "Road vehicle running on tracks" , "multi-faceted yarn" .)