Trade in vehicle I parked by headland (8)
I believe the answer is:
business
'trade' is the definition.
(thesaurus)
'vehicle i parked by headland' is the wordplay.
'vehicle' becomes 'bus' (I've seen this before).
'parked by' says to put letters next to each other.
'headland' becomes 'ness' (I've seen this before).
'bus'+'i'+'ness'='BUSINESS'
'in' is the link.
(Other definitions for business that I've seen before include "See 1" , "Company U occupation" , "Commerce, trace" , "Commercial unit or activity" , "Affair - matters to be attended to" .)