Obsession of a man needing an excellent rise (5)
I believe the answer is:
mania
'obsession' is the definition.
(thesaurus)
'of a man needing an excellent rise' is the wordplay.
'of' becomes 'ma' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'a man' becomes 'n' (knight, a man in chess).
'needing' is a charade indicator (letters next to each other).
'an excellent' becomes 'ai'.
'rise' says the letters should be written in reverse.
'ai' back-to-front is 'ia'.
'ma'+'n'+'ia'='MANIA'
Can you help me to learn more?
(Other definitions for mania that I've seen before include "Obsessional enthusiasm" , "Obsessive enthusiasm" , "Frenzy" , "Passion -- mood disorder" , "Aberration" .)