Concerning money at university, first expense being train (7)
I believe the answer is:
retinue
'being train' is the definition.
(people following someone in a procession)
'concerning money at university first expense' is the wordplay.
'concerning money' becomes 'ret' (I am not sure about this - if you are sure you should believe this answer much more).
'at' becomes 'in'.
'university' becomes 'u' (abbreviation for university).
'first expense' becomes 'e' (rst letter of 'expense').
'ret'+'in'+'u'+'e'='RETINUE'
Can you help me to learn more?
(Other definitions for retinue that I've seen before include "Body of aides" , "Group attending a person" , "VIP's attendants" , "Train, escort" , "Group of attendants for VIP" .)