Venus Williams' sport (6)
I believe the answer is:
tennis
'venus williams' sport' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tennis that I've seen before include "Racket-and-ball game" , "Sport Dwight Davis gave trophy for" , "Ball-game" , "Racquet sport" , "Game of the Williams sisters and of Roger Federer" .)