Hip-hop repertory (4)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">hip-hop repertory</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for raps that I've seen before include "Knocks sharply" , "Cracks" , "'Knocks, on the door say (4)'" , "Sprechgesang pop hits" .)