Began; undone (6)
I believe the answer is:
opened
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">began</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(opening is a kind of beginning)</span><br/ ><br/ >'<span class="explanation-format__original">undone</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(opening is a kind of undoing)</span><br/ ><br/ ></span>
(Other definitions for opened that I've seen before include "starting the game" , "Began - undone" , "Started, a meeting say" , "Made available" , "Unlocked or unfolded" .)