The colour of unbleached linen (4)
I believe the answer is:
ecru
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">the colour of unbleached linen</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for ecru that I've seen before include "Buff or beige" , "Natural stuff" , "Strange cure for a colour" , "one of the colours" , "No bright colour" .)