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n. A bitter compound used in adulterating beer.

n. A bitter compound used in adulterating beer; bittern.

n. Same as bittern, 2.

n. The acquiring by wine of a bitter flavor, due to the formation of brown aldehyde resin or other bitter substance, from age or high temperature.

"In beer parlance, there are two kinds of hops: one that tones down the sweetness, known as a bittering hop, and another that is added closer to he end of the brewing process, called an aroma hop, that gives beers their distinct flavor."

bittern   

bitter