Corpse Dave found in vehicle (7)
I believe the answer is:
cadaver
'corpse' is the definition.
(synonyms)
'dave found in vehicle' is the wordplay.
'found in' means one lot of letters goes inside another.
'vehicle' becomes 'car' (car is a kind of vehicle).
'dave' going into 'car' is 'CADAVER'.
(Other definitions for cadaver that I've seen before include "Dead body, corpse" , "Human corpse" , "A kind of corpse" , "Remains of a human" , "Dead human body" .)