They're left behind (7)
I believe the answer is:
estates
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">they're left behind</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for estates that I've seen before include "Large cars" , "Demesnes" , "Country properties" , "Cars with rear doors" , "People leave them" .)