Groups of singers (6)
I believe the answer is:
choirs
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">groups of singers</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 choirs that I've seen before include "Bands of singers" , "Singing teams" , "Groups of singers, in church say" , "Groups of singers, often in churches" , "Singing groups" .)