Originally South American music, Brazilian actually (5)
I believe the answer is:
samba
'originally south american music brazilian actually' is the definition.
'originally south american music brazilian actually' is the wordplay.
'originally' suggests taking the first letters.
The first letters of 'south american music brazilian actually' is 'SAMBA'.
(Other definitions for samba that I've seen before include "Dance music" , "Lively ballroom dance from Brazil" , "moves from Brazil" , "it was launched in Brazil" , "Dance, originally from Brazil" .)