Group of eight musicians (5)
I believe the answer is:
octet
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">group of eight musicians</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for octet that I've seen before include "Eight people together" , "Musical group" , "Music for eight" , "Group of eight players" , "A group of eight, may be singers" .)