Bathroom, in brief (3)
I believe the answer is:
lav
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bathroom in brief</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 lav that I've seen before include "Private place in short" , "toilet" , "Loo" .)