Great merriment (4)
'great merriment' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for glee that I've seen before include "Type of club" , "Old English part-song" , "much fun" , "Impish enjoyment" , "Unholy delight" .)
(Other definitions for mirth that I've seen before include "Jocularity" , "Merriment" , "Laughter" , "Hilarity" , "Glee" .)