Mournful song form trio about fellow suffering setback (8)
I believe the answer is:
threnode
'mournful song form' is the definition.
The definition suggests a singular noun which matches the answer.
'trio about fellow suffering setback' is the wordplay.
'trio' becomes 'three' (synonyms).
'about' means one lot of letters goes inside another.
'fellow' becomes 'don' (both can mean an academic).
'suffering setback' shows that the letters should be reversed in order.
'don' written backwards gives 'nod'.
'three' enclosing 'nod' is 'THRENODE'.
Can you help me to learn more?
(Another definition for threnode that I've seen is " Lament".)