Cola or ginger ale (4)
I believe the answer is:
soda
'cola or ginger ale' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for soda that I've seen before include "Variety of pop" , "Mixer drink" , "Fizzy drink - chemical compound" , "In the US, a sweet fizzy drink" , "Type of bread, water or fountain" .)