Some trouble I routinely encountered back in college (5)
I believe the answer is:
oriel
'college' is the definition.
(Oxford University college)
'some trouble i routinely encountered back' is the wordplay.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'back' is a reversal indicator.
'leiro' is hidden within 'trouble i routinely encountered'.
'leiro' in reverse letter order is 'ORIEL'.
'in' acts as a link.
(Other definitions for oriel that I've seen before include "English college" , "Upper-story bay window" , "Recessed bay window" , "Loire (anag.)" , "lecturer seen near Lorraine regularly" .)