Ska relative (6)
I believe the answer is:
reggae
'ska relative' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for reggae that I've seen before include "Music style from Jamaica" , "Bob Marley music" , "West Indian music with strong subsidiary beat" , "W.I. music" , "Bob Marley's music" .)