Not bright or clear (5)
I believe the answer is:
muddy
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">not bright or clear</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 muddy that I've seen before include "Covered in mire" , "Slimy" , "Not bright or clear" , "Mucky, marshy" , "Bespattered" .)