Singing voice; fish (4)
I believe the answer is:
bass
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">singing voice</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that bass is a type of singing voice)</span><br/ ><br/ >'<span class="explanation-format__original">fish</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(bass is a kind of fish)</span><br/ ><br/ ></span>
(Other definitions for bass that I've seen before include "Fish; male singing voice" , "Type of fish" , "Fish; vocalist" , "Fish, guitar" , "Lowest adult male singing voice" .)