A limit restricting small cat with energy drink (4,8)
I believe the answer is:
asti spumante
'drink' is the definition.
(I've seen this before)
'a limit restricting small cat with energy' is the wordplay.
I cannot really see how this works, but
'a' could be 'an' and 'an' is present in the answer.
'small' could be 's' (abbreviation - e.g. clothes size) and 's' is found in the answer.
'energy' could be 'e' (physics symbol as in E=mc2) and 'e' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for asti spumante that I've seen before include "Italian sparking wine" , "Man is upstate (anag.)" , "drink" .)