Group of fish (5)
I believe the answer is:
shoal
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">group of fish</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 shoal that I've seen before include "Swarm of fish" , "Large group of fish - sandbank" , "Fish grouped" , "A great number of fish swimming together" , "Collection of fish" .)