Festive song (5)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
carol
'festive song' is the definition.
This is all the clue.
(Other definitions for carol that I've seen before include "Girl" , "Christmas ditty" , "sing happily" , "Joyful song - girl's name" , "Canticle" .)