Show-off scholar (6)
I believe the answer is:
pedant
'show-off scholar' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for pedant that I've seen before include "One particular" , "one of the old school?" , "Stickler for minor details" , "Person who is strict on rules and details" , "Know-all who insists on strict observance of rules" .)