Numbered composition (4)
I believe the answer is:
opus
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">numbered composition</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 opus that I've seen before include "(Numbered) musical composition" , "Artistic work" , "Showing creative skill" , "Work (mus.)" , "Musical composition in the soup" .)