noun
also kvas kəˈväs, ˈkfäs ; or quass or quas “, ˈkwäs
( -es )
Etymology: Russian kvas; akin to Old Slavic kvasŭ sour drink — more at cheese
: a weak homemade beer of Eastern European countries (as Russia) made by pouring warm water over a mixture of cereals and allowing it to ferment