Rome's river (5)
I believe the answer is:
tiber
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">rome's river</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 tiber that I've seen before include "Roman river" , "divides Rome" , "Italian banker" , "The flower of Rome" , "River of Rome" .)