Remove the chaff (6)
I believe the answer is:
thresh
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">remove the chaff</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for thresh that I've seen before include "Separate grain from (eg, corn)" , "as one may having crop" , "Separate seed from grain" , "Extract grain (with flail)" , "Separate corn from husks by beating" .)