A black and white bird (6)
I believe the answer is:
magpie
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">a black and white bird</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 magpie that I've seen before include "Part of target" , "Ominous bird if seen alone" , "Long-tailed crow" , "Black and white member of crow family" , "chatty bird" .)