Relating to ethnicity (6)
I believe the answer is:
racial
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">relating to ethnicity</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 racial that I've seen before include "Relating to ethnic group" , "Relating to ethnicity" , "Relating to ethnic divisions" , "Of particular people or colour, as with prejudice" , "on coloured lines?" .)