Cornish city (5)
I believe the answer is:
truro
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cornish city</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for truro that I've seen before include "Cornish county town" , "City of Cornwall" , "Cornish cathedral city" , "Cape Cod town: county town of Cornwall" , "Southwest city" .)