Reputation turning into a tricky issue (9)
I believe the answer is:
emanation
'issue' is the definition.
(thesaurus)
'reputation turning into a tricky' is the wordplay.
'reputation' becomes 'name' (name is a kind of reputation**).
'turning' says the letters should be written backwards.
'tricky' indicates an anagram.
'name' back-to-front is 'eman'.
'into'+'a'='intoa'
'intoa' anagrammed gives 'ation'.
'eman'+'ation'='EMANATION'
(Other definitions for emanation that I've seen before include "Something flowing out from a source" , "Something issuing from a source" , "Pouring out" , "Something produced from a source" , "Issue" .)