Drink cubes (3)
I believe the answer is:
ice
'drink cubes' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ice that I've seen before include "Diamonds (informal)" , "Diamonds, colloquially" , "Cooler" , "Decorate with frosting" , "It's cold and slippy" .)