Many a complicated issue means waste (6)
I believe the answer is:
misuse
'waste' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'many a complicated issue' is the wordplay.
'many' becomes 'm' (Roman numeral for a thousand).
'a complicated' indicates anagramming the letters.
'issue' anagrammed gives 'isuse'.
'm'+'isuse'='MISUSE'
'means' is the link.
Can you help me to learn more?
(Other definitions for misuse that I've seen before include "Treat badly, unfairly" , "Employ or apply wrongly" , "bad treatment" , "Wrongful employment" , "exploitation" .)