Volcanic residue (3)
I believe the answer is:
ash
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">volcanic residue</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 ash that I've seen before include "One [TYPE OF TREE]" , "Remnant from fire" , "Fraxinus" , "Tree in danger" , "Burnt remains; tree" .)