Fool at university could be swot (3,2)
I believe the answer is:
mug up
'be swot' is the definition.
(I've seen this before)
'fool at university' is the wordplay.
'fool' becomes 'mug' (synonyms).
'at university' becomes 'up' ('up' can mean studying at university).
'mug'+'up'='MUG UP'
'could' is the link.
(Other definitions for mug up that I've seen before include "Learn (subject) quickly" , "Cram" , "do emergency study" , "Study intensively" , "Study; revise" .)