Roberts's co-star in "Pretty Woman” (4)
I believe the answer is:
gere
'roberts's co-star in pretty woman' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for gere that I've seen before include "Richard - - , film star" , "Surname of actor" , "US actor" , "Richard - - (filmstar)" .)