Loud metallic sound (5)
I believe the answer is:
clang
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">loud metallic sound</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 clang that I've seen before include "Loud resonant metallic sound" , "Dull sound of a bell" , "Metallic ring" , "Noise as of cymbals" , "Resounding effect" .)