Operations room! (7)
I believe the answer is:
theatre
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">operations room</span>' is the definition.<br/ ><span class="explanation-format__explanation">(where surgical operations are carried out)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for theatre that I've seen before include "where they're in action?" , "(Military) field of action" , "(Lecture) room" , "Space for dramatic art and surgery" , "Space for dramatid art" .)