Shortly choose holding final credit cards? (7)
I believe the answer is:
plastic
'cards?' is the definition.
(I've seen this before)
'shortly choose holding final credit' is the wordplay.
'shortly' means to remove the last letter.
'choose' becomes 'pick' (picking is a kind of choosing).
'holding' is an insertion indicator.
'final credit' becomes 'last' (I can't justify this - if you can you should give a lot more credence to this answer).
'pick' with its last letter removed is 'pic'.
'pic' enclosing 'last' is 'PLASTIC'.
Can you help me to learn more?
(Other definitions for plastic that I've seen before include "Artificial; easily moulded" , "Mouldable material" , "Credit cards etc" , "Flexible - synthetic material" , "Credit card; mouldable" .)