Anaesthetised (5)
I believe the answer is:
under
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">anaesthetised</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for under that I've seen before include "Governed by" , "In the process of" , "Anaesthetised" , "Subject to the authority of" , "See 7" .)