Swimming actress Williams (6)
I believe the answer is:
'swimming actress williams' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for esther that I've seen before include "Beautiful lady" , "__ Rantzen, TV presenter, b. 1940" , "Girl's name; OT book" , "Holy Book" , "OT heroine" .)