Arrogant poke round university (5)
I believe the answer is:
proud
'arrogant' is the definition.
(similar in meaning)
'poke round university' is the wordplay.
'poke' becomes 'prod' (synonyms).
'round' is an insertion indicator.
'university' becomes 'u' (abbreviation for university).
'prod' going around 'u' is 'PROUD'.
(Other definitions for proud that I've seen before include "Self-respecting or self-important" , "Conscious of one's own dignity" , "Self-satisfied - arrogant" , "Self-respect, feeling of self-worth" , "Slightly projecting; imposing" .)