Forerunner of reggae (3)
I believe the answer is:
ska
'forerunner of reggae' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for ska that I've seen before include "Noted genre" , "Music genre" , "Dancehall music" , "Jamaican music, forerunner of reggae" , "popular music" .)