Robust second wine, measure of its strength? (10)

'robust' is the definition.
Both the answer and definition are adjectives.
Perhaps you can see a link between them that I don't see?

'second wine measure of its strength?' is the wordplay.
I cannot really see how this works, but
'second' could be 's' (common abbreviation) and 's' is found in the answer.
'wine' could be 'hock' (type of wine) and 'hock' is located in the answer.
'measure' could be 'proof' (proof is a kind of measure) and 'proof' is present in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?