Nothing in tennis (4)
I believe the answer is:
love
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">nothing in tennis</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for love that I've seen before include "Intense affection" , "Nil score in 19" , "No points" , "Score of zero at tennis" , "Vole (anag.)" .)