Articles on European Union kept by fellow returning to old seat of learning (9)
I believe the answer is:
athenaeum
'old seat of learning' is the definition.
I can't tell whether this definition defines the answer.
'articles on european union kept by fellow returning' is the wordplay.
'articles on' becomes 'athe' (two examples of the part-of-speech: a+the. I am not sure about the 'on' bit.).
'european union' becomes 'eu'.
'kept by' is an insertion indicator.
'fellow' becomes 'man' (I've seen this before).
'returning' says the letters should be written backwards.
'man' back-to-front is 'nam'.
'eu' put inside 'nam' is 'naeum'.
'athe'+'naeum'='ATHENAEUM'
'to' acts as a link.
Can you help me to learn more?
(Another definition for athenaeum that I've seen is " London club for the learned".)