Nefarious (4)
I believe the answer is:
evil
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">nefarious</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for evil that I've seen before include "Malignant" , "Extremely bad" , "Wicked or immoral" , "mischief" , "A live sort of badness" .)