Pub, heavy drinker (6)
I believe the answer is:
boozer
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">pub</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(boozer can informally mean a pub)</span><br/ ><br/ >'<span class="explanation-format__original">heavy drinker</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ ></span>
(Other definitions for boozer that I've seen before include "Inn" , "Heavy drinker" , "Pub (sl.)" , "Pub (slang)" .)