Body in vehicle about to join ship (7)
I believe the answer is:
carcass
'body' is the definition.
(I know that Carcass is a type of body)
'vehicle about to join ship' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'about' becomes 'ca' (circa).
'to join' is a charade indicator (letters next to each other).
'ship' becomes 'SS' (prefix in ship names eg SS Great Britain).
'car'+'ca'+'ss'='CARCASS'
'in' is the link.
(Other definitions for carcass that I've seen before include "Dead animal's body" , "Framework" , "Dead body of animal" .)