Lacking in colour (7)
I believe the answer is:
anaemic
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">lacking in colour</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for anaemic that I've seen before include "strangely pale" , "Pale, lacking vitality" , "Pale, weak in colour" , "Lacking vigour as in a cinema" , "Lacking in colour/vitality" .)