Brunch cocktail with champagne and OJ (6)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
mimosa
(Other definitions for mimosa that I've seen before include "Tree with scented clustered flowers" , "Tropical tree or shrub with clusters of fragrant flowers" , "Sensitive thing growing" , "Variety of acacia" , "Yellow-flowered acacia tree" .)