Music has special capacity at first (3)
I believe the answer is:
ska
'music' is the definition.
(music genre)
'special capacity at first' is the wordplay.
'special capacity' becomes 'sk' (I can't explain this - if you can you should believe this answer much more).
'at first' becomes 'a' (sst letter of 'at').
'sk'+'a'='SKA'
'has' acts as a link.
Can you help me to learn more?
(Other definitions for ska that I've seen before include "Jamaican music, forerunner of reggae" , "popular music" , "Music genre" , "Dancehall music" , "Noted genre" .)