Fuss at a party (3)
I believe the answer is:
ado
'fuss' is the definition.
(synonyms)
'at a party' is the wordplay.
'at' is a charade indicator (letters next to each other).
'party' becomes 'do' (do can informally mean a party).
'a' put next to 'do' is 'ADO'.
(Other definitions for ado that I've seen before include "flapping" , "Fuss, trouble" , "Goings-on" , "Song and dance" , "hoo-hah" .)