Boy in relaxed state about university (5)
I believe the answer is:
calum
'boy' is the definition.
(boy's name)
'in relaxed state about university' is the wordplay.
'in relaxed state' becomes 'calm' (calm means relaxed).
'about' is an insertion indicator.
'university' becomes 'u' (abbreviation for university).
'calm' going around 'u' is 'CALUM'.
(Other definitions for calum that I've seen before include "Scotsman" , "Irishman" .)