Monster — huge thing (8)
I believe the answer is:
behemoth
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">monster</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >'<span class="explanation-format__original">huge thing</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ ></span>
(Other definitions for behemoth that I've seen before include "Something huge and monstrous" , "Anything abnormally large and powerful" , "Abnormally large creature" , "Something abnormally large and powerful" , "Something of impressive size or power" .)