Disappear; evaporate (6)
I believe the answer is:
vanish
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">disappear</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that disappear can be written as vanish)</span><br/ ><br/ >'<span class="explanation-format__original">evaporate</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that evaporate can be written as vanish)</span><br/ ><br/ ></span>
(Other definitions for vanish that I've seen before include "Become invisible" , "Cease to exist" , "Go missing" , "Evanesce" , "make go" .)