Dance band's leader has everything (4)
I believe the answer is:
ball
'dance' is the definition.
(ball is a kind of dance)
'band's leader has everything' is the wordplay.
'leader' says to take the initial letters.
'has' is a charade indicator (letters next to each other).
'everything' becomes 'all' (all things).
The first letter of 'bands' is 'b'.
'b'+'all'='BALL'
(Other definitions for ball that I've seen before include "Formal dance gathering" , "One spotted in competition" , "Social function for dancing" , "Sphere for sport" , "Perhaps a bouncer < 's clog" .)