Intense — sharp (8)
I believe the answer is:
piercing
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">intense</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">sharp</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that sharp can be written as piercing)</span><br/ ><br/ ></span>
(Other definitions for piercing that I've seen before include "very loud" , "Shrill" , "Making a hole in (something)" , "Very cold (wind)" , "Ear-splitting" .)