Harsh — radical (7)
I believe the answer is:
drastic
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">harsh</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">radical</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(drastic can mean radical or extreme)</span><br/ ><br/ ></span>
(Other definitions for drastic that I've seen before include "'Dramatic, extreme (7)'" , "Severe and far-reaching" , "Very severe or serious" , "Severe, radical (measures)" , "Extremely severe" .)