Approach continuous period at university (3-2)
I believe the answer is:
run-up
'approach' is the definition.
(I know that run-up is a type of approach)
'continuous period at university' is the wordplay.
'continuous period' becomes 'run' (run can mean a sequence of things).
'at university' becomes 'up' (slang term meaning at university).
'run'+'up'='RUN-UP'
(Other definitions for run-up that I've seen before include "Approach - preliminaries" , "Preliminary period" , "Cricketing approach?" , "Bowler's approach?" .)