Excludes, obstructs (4)
I believe the answer is:
bars
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">excludes</span>' is the first definition.<br/ ><span class="explanation-format__explanation">('bar' can be a synonym of 'exclude')</span><br/ ><br/ >'<span class="explanation-format__original">obstructs</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(barring is a kind of obstructing)</span><br/ ><br/ ></span>
(Other definitions for bars that I've seen before include "Rods or drink dispensers" , "Prohibits; pubs" , "Drinking holes; prohibits" , "Metal rods or pubs" , "Obstacles" .)