KEG Meaning of KEG in English [keg] n [ME kag, of Scand origin; akin to ON kaggi keg] (ca. 1632) 1: a small cask or barrel having a capacity of 30 gallons (136.4 liters) or less 2: the contents of a keg Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012