Cause the ruin of (2,3)
(Other definitions for do for that I've seen before include "suit" , "Destroy or kill" , "Ruin" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cause the ruin of</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 undo that I've seen before include "Ruin or loose" , "Unfasten, loosen" , "Ruin, destroy" , "Open button or ruin" , "Open or unfasten" .)