Express disapproval about university displaying source of ivory (4)
I believe the answer is:
tusk
'source of ivory' is the definition.
(I've seen this before)
'express disapproval about university' is the wordplay.
'express disapproval' becomes 'tsk' (I can't explain this - if you can you should believe this answer much more).
'about' means one lot of letters goes inside another.
'university' becomes 'U' (abbreviation for university).
'tsk' enclosing 'u' is 'TUSK'.
'displaying' acts as a link.
Can you help me to learn more?
(Other definitions for tusk that I've seen before include "What's the point of a Jumbo that's hard" , "An elephant's long tooth" , "Protruding ivory, of elephant say" , "Elongated tooth" , "Ivory-coloured dentine" .)