Oscar-winner Thompson (4)
I believe the answer is:
emma
'oscar-winner thompson' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for emma that I've seen before include "Retired chief in Ian Fleming" , "Best Actress Oscar winner 1992, for 'Howard's End'" , "heroine of novel" , "Title of novel by Jane Austen" , "book" .)