Miss a party (4)
I believe the answer is:
gala
'party' is the definition.
(thesaurus)
'miss a' is the wordplay.
'miss' becomes 'gal' ('gal' can be a synonym of 'miss').
'gal'+'a'='GALA'
(Other definitions for gala that I've seen before include "Festivity - celebration" , "Festive entertainment" , "Public festivity" , "Festive occasion - variety of apple" , "Mix" .)