Shed light on, clarify (9)
I believe the answer is:
elucidate
I believe this is a double definition.
'shed light on' is the first definition.
(synonyms)
'clarify' is the second definition.
(I know that elucidate is a more specific form of the action clarify)
(Other definitions for elucidate that I've seen before include "Throw light on a problem, make clear (9)" , "Make clear, explain" , "Make clear and more comprehensible" , "Shed light upon" , "Shed light on, clarify" .)