Ancient city; system of weights (4)
I believe the answer is:
troy
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">ancient city</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(Troy was an ancient city)</span><br/ ><br/ >'<span class="explanation-format__original">system of weights</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(troy is a kind of system of weights)</span><br/ ><br/ ></span>
(Other definitions for troy that I've seen before include "Ancient city; type of weight" , "Wooden horse siege city" , "Ancient city of the Iliad" , "System of weights for precious stones and metals" , "Iliad siege city" .)