Greek underworld
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">greek underworld</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 hades that I've seen before include "Greek underworld with spirits of the dead" , "Home of the souls of the dead" , "In Greek myth, the Underworld" , "Infernal situation" , "It's hell in the Greek shade" .)