Canteen (9)
I believe the answer is:
cafeteria
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">canteen</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for cafeteria that I've seen before include "Self-service eating place" , "eating-place" , "greasy spoon?" , "Self-service restaurant" , "Where one scoffs" .)