Prohibit, exclude (5)
I believe the answer is:
debar
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">prohibit</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(debarring is a kind of prohibiting)</span><br/ ><br/ >'<span class="explanation-format__original">exclude</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ ></span>
(Other definitions for debar that I've seen before include "Rule out" , "Formally prevent" , "Exclude - bread (anag)" , "Block" , "Black" .)