Ball belle (3)
I believe the answer is:
deb
'ball belle' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for deb that I've seen before include "Young socialite" , "Young woman making her first appearance in society, in short" , "One coming out" , "In brief, a society girl getting out of bed" , "Girl just entering society" .)