Threat, danger (6)
I believe the answer is:
menace
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">threat</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >'<span class="explanation-format__original">danger</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(menace is a kind of danger)</span><br/ ><br/ ></span>
(Other definitions for menace that I've seen before include "A source of danger" , "peril" , "Threat or severe nuisance" , "Threat; threaten" , "Threaten with harm or danger" .)