Intimidating, threatening (8)
I believe the answer is:
menacing
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">intimidating</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >'<span class="explanation-format__original">threatening</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that threatening can be written as menacing)</span><br/ ><br/ ></span>
(Other definitions for menacing that I've seen before include "Ominous" , "Intimidating" , "Scary" , "Threatening" , "Suggesting danger" .)