Small and dainty (6)
I believe the answer is:
'small and dainty' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for petite that I've seen before include "Elfin" , "Short" , "Tie pet up, being small and dainty" , "Small and dainty from France" , "Small, slim (girl)" .)