Whitened (8)
I believe the answer is:
bleached
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">whitened</span>' is the definition.<br/ ><span class="explanation-format__explanation">(bleaching is a kind of whitening)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for bleached that I've seen before include "Chemically whitened" , "Paled" , "Whitened or removed colour from" .)