Royal racecourse (5)
I believe the answer is:
ascot
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">royal racecourse</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 ascot that I've seen before include "Racecourse with royal associations" , "racing centre" , "Tosca (anag) - racecourse" , "course without any fences!" , "Berkshire racecourse - coast (anag)" .)