Cancel out (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cancel out</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for nullify that I've seen before include "Declare invalid" , "Make invalid" , "Render void" , "Render ineffective" , "Bring to naught" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cancel out</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 negate that I've seen before include "Disprove or nullify" , "Age ten (anag)" , "Make invalid" , "disallow!" , "Show to be false" .)