He has a fish for curing (7)
I believe the answer is:
healing
'curing' is the definition.
('heal' can be a synonym of 'cure')
'he has a fish for' is the wordplay.
'has' says to put letters next to each other.
'fish for' becomes 'ling' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'he'+'a'+'ling'='HEALING'
Can you help me to learn more?
(Other definitions for healing that I've seen before include "Recovering, becoming healthy" , "Mending" , "Curative" , "Getting better" , "Restoring to health" .)