From non- + sound. <span class="searchmatch">nonsound</span> (countable and uncountable, plural <span class="searchmatch">nonsounds</span>) That which is not sound (something audible). 1988, Lynne Anne Blom, L. Tarin...
<span class="searchmatch">nonsounds</span> plural of <span class="searchmatch">nonsound</span>...