Civil rights activist Simone (4)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
nina
(Other definitions for nina that I've seen before include "hidden crossword message" , "Girl" , "Al Hirschfeld's 'hidden' daughter" , "- Simone, US singer" , "One of Columbus's ships in 1492; girl's name" .)