• (n.) A thin, sour beer, made by pouring warm water on rye or barley meal and letting it ferment, -- much used by the Russians.
Quass noun [ Russian kvas' .] A thin, sour beer, made by pouring warm water on rye or barley meal and letting it ferment, -- much used by the Russians. [ written also quas .]
Quass (Kvass) is a sour, fermented liquor made by pouring warm water on rye or barley meal. It was popular in Russia amongst the peasantry.