Not this or that (7)
I believe the answer is:
neither
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">not this or that</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for neither that I've seen before include "Not one thing or the other" , "In three (anag.)" , "Therein lies not one or the other" , "Therein (anag)" , "both are rejected" .)