At least a dozen answer, giving approval (4)
I believe the answer is:
visa
'approval' is the definition.
(I know that visa is a type of countenance)
'at least a dozen answer' is the wordplay.
I cannot quite see how this works, but
'a' is found in the answer.
The remaining letters 'vis' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'giving' is the link.
Can you help me to learn more?
(Other definitions for visa that I've seen before include "Endorsement allowing bearer to enter country" , "giving you access to capital?" , "Passport stamp or well-known credit card" , "ID" , "Travel permit stamped in passport etc" .)