Definitions for kvasskvɑs, kwɑs
Random House Webster's College Dictionary
a Russian drink with a low alcoholic content made from fermented cereal or bread.
Origin of kvass:
1545–55; < Russ kvas
fermented beverage resembling beer but made from rye or barley
A type of traditional fermented Russian beverage with little or no alcohol, made from bread, often flavored with fruit.
Origin: From квас.