Concealed or secret (6)
I believe the answer is:
covert
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">concealed</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ >'<span class="explanation-format__original">secret</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ ></span>
(Other definitions for covert that I've seen before include "Concealed, like fox's lair" , "place for game" , "Concealed, secret" , "Not acknowledged" , "in this secret place?" .)