Wager everyone comes in to dance (6)
I believe the answer is:
ballet
'dance' is the definition.
(ballet is a kind of dance)
'wager everyone comes in' is the wordplay.
'wager' becomes 'bet' (synonyms).
'everyone' becomes 'all' (all people).
'comes in' means one lot of letters goes inside another.
'bet' going around 'all' is 'BALLET'.
'to' is the link.
(Other definitions for ballet that I've seen before include "Art of the Kirov or Bolshoi" , "kind of skirt" , "Eg, Swan Lake" , "old madrigal" , "Classical dancing style" .)