Body of Dad's son found in car (7)
I believe the answer is:
'body' is the definition.
(I know that body can be written as cadaver)
'dad's son found in car' is the wordplay.
'dad's son' becomes 'dave' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'found in' means one lot of letters goes inside another.
'dave' inserted into 'car' is 'CADAVER'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for cadaver that I've seen before include "Remains of a human" , "Human corpse" , "Dead human body" , "Human body dissected by medical students" , "A kind of corpse" .)