Noisy insects (7)
I believe the answer is:
cicadas
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">noisy insects</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 cicadas that I've seen before include "Noisy insects" , "These insects have an acid sac" .)