What's reversing behind big black car? (6)
I believe the answer is:
hearse
'black car?' is the definition.
(car used in a funeral procession)
'what's reversing behind' is the wordplay.
'what' becomes 'eh' (sound used to ask 'what?' or 'pardon?').
'reversing' is a reversal indicator.
'behind' becomes 'arse' (both can mean the buttocks).
'eh' reversed gives 'he'.
'he'+'arse'='HEARSE'
'big' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for hearse that I've seen before include "Vehicle for the last trip?" , "Vehicle to carry a coffin" , "Funeral car" , "Last time transport" , "Vehicle for carrying the dead" .)