Festivity, fun (7)
I believe the answer is:
revelry
I believe this clue is a double definition.
'festivity' is the first definition.
(I know that revelry is a type of conviviality)
'fun' is the second definition.
(thesaurus)
(Other definitions for revelry that I've seen before include "Jolly parties" , "Riotous feasting" , "Feasting, noisy festivities" , "Merrymaking" , "Noisy celebration" .)