Tennis playing area (5)
I believe the answer is:
court
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">tennis playing area</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 court that I've seen before include "invite > defendant to appear here" , "Assembly to conduct 12 across" , "Legal or royal assembly" , "Woo - where tennis is played" , "Sports area; woo" .)