Come back in (7)
I believe the answer is:
reenter
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">come back in</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 reenter that I've seen before include "Come back inside" , "Go in again" , "Penetrate again" , "Go/come in again" , "Terrene (anag.)" .)