Swanky party (4)
I believe the answer is:
gala
'swanky party' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for gala that I've seen before include "Festivity - celebration" , "Festive entertainment" , "Special social or sporting occasion" , "Festive event" , "Festive occasion - variety of apple" .)