Dance beat at grand ball (5)
I believe the answer is:
tango
'dance' is the definition.
(tangoing is a kind of dancing)
'beat at grand ball' is the wordplay.
'beat' becomes 'tan' (I've seen this before).
'at' means one lot of letters go next to another.
'grand' becomes 'g' ('G' can be a synonym of 'grand').
'ball' becomes 'o'.
'tan'+'g'+'o'='TANGO'
(Other definitions for tango that I've seen before include "Steps" , "Argentinian dance form" , "Dramatic ballroom dance from Argentina" , "musical piece" , "Rhythmic movement" .)