Unsoiled (5)
I believe the answer is:
clean
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">unsoiled</span>' is the definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for clean that I've seen before include "Unsoiled" , "Wash" , "Non-polluting" , "Pure; well-defined" , "Second part of 18" .)