1. (noun)barium, Ba, atomic number 56 a soft silvery metallic element of the alkali earth group; found in barite Synonyms: barium, atomic number 56
2. (noun)Bachelor of Arts, BA, Artium Baccalaurens, AB a bachelor's degree in arts and sciences Synonyms: type AB, abdominal, barium, group AB, abdominal muscle, atomic number 56