Girl in green (5)
I believe the answer is:
I believe this clue is a double definition.
'girl' is the first definition.
'green' is the second definition.
(I know that olive is a type of green)
'in' is the link.
(Other definitions for olive that I've seen before include "girl" , "Stoned fruit" , "Tree - shade of green" , "It's branch is a symbol of peace" , "Yellowish-green - fruit" .)