Capital city of Spain (6)
I believe the answer is:
madrid
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">capital city of spain</span>' is the definition.<br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for madrid that I've seen before include "Spain's capital" , "City with the Prado national art gallery" , "European capital city" , "Spanish capital" , "Spanish city" .)