Not either (7)
I believe the answer is:
neither
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">not either</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for neither that I've seen before include "both are rejected" , "Therein (anag)" , "Not one of two" , "And not; nor yet" , "Negative word" .)