Girl in the song (5)
I believe the answer is:
carol
I believe this is a double definition.
'girl' is the first definition.
(woman's name)
'song' is the second definition.
(carol is a kind of song)
'in the' is the link.
(Other definitions for carol that I've seen before include "Female" , "Girl's name; sing" , "Canticle" , "Girl" , "Joyful religious song" .)