The Collaborative International Dictionary of English v.0.48:
Drinkable \Drink"a*ble\, a. Capable of being drunk; suitable for drink; potable. --Macaulay. Also used substantively, esp. in the plural. --Steele. [1913 Webster]WordNet (r) 3.0 (2006):
drinkable adj 1: suitable for drinking [syn: drinkable, potable] [ant: undrinkable] n 1: any liquid suitable for drinking; "may I take your beverage order?" [syn: beverage, drink, drinkable, potable]