Dance held by generous ambassador (5)
I believe the answer is:
samba
'dance' is the definition.
(Brazilian dance)
'held by generous ambassador' is the wordplay.
'held by' indicates the answer is hidden within the clue.
'SAMBA' is hidden in the letters of 'generous ambassador'.
(Other definitions for samba that I've seen before include "Brazilian dance" , "moves from Brazil" , "Lively ballroom dance from Brazil" , "This ambassador's > brisk steps" , "Dance, originally from Brazil" .)