Cure, make healthy (4)
I believe the answer is:
heal
I believe this clue is a double definition.
'cure' is the first definition.
(synonyms)
'make healthy' is the second definition.
(I've seen this before)
(Other definitions for heal that I've seen before include "Cure, restore" , "Get healthy again" , "Make better" , "Become healthy again" , "Cure, recover" .)