Devise a scheme, say, to support son using cars? (10)
I believe the answer is:
hatchbacks
'cars?' is the definition.
(hatchback is a kind of car)
'devise a scheme say to support son' is the wordplay.
'devise' becomes 'hatch' (as in hatching a plan).
'a scheme say' becomes 'back' (I can't justify this - if you can you should give a lot more credence to this answer).
'to support' means one lot of letters go next to another (in a down clue, some letters hold others up).
'son' becomes 's' (genealogical abbreviation for son).
'hatch'+'back'+'s'='HATCHBACKS'
'using' is the link.
Can you help me to learn more?
(Another definition for hatchbacks that I've seen is " vehicles".)