Class hosting university meeting (5)
I believe the answer is:
forum
'meeting' is the definition.
(forum is a kind of meeting)
'class hosting university' is the wordplay.
'class' becomes 'form' (form class is a kind of class).
'hosting' indicates putting letters inside (inserted letters are welcomed in or hosted).
'university' becomes 'U' (abbreviation as in UMass).
'form' placed around 'u' is 'FORUM'.
(Other definitions for forum that I've seen before include "Medium for discussion" , "Place to discuss ideas" , "Public meeting or assembly for open discussion" , "old square" , "Tribunal" .)