A cold fish admitting the woman's vulnerability (8,4)
I believe the answer is:
achilles heel
'vulnerability' is the definition.
(I've seen this before)
'a cold fish admitting the woman's' is the wordplay.
I cannot quite see how this works, but
'a' is found in the answer.
'cold' could be 'chill' (chill can mean cold) and 'chill' is found within the answer.
'fish' could be 'eel' (eel is a type of fish) and 'eel' is found 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 achilles heel that I've seen before include "Small but crucial weakness" , "Person's vulnerable weakness" , "Vulnerable part" , "flaw" , "One's most vulnerable spot" .)