barium oxide barium nitrate • barium peroxide · · · Info · Definitions · Synonyms · Characters · · barium oxide · · Text Common · · Latin · · Scripts 12 · · Length Definitions · · · (noun) an oxide of barium; a whitish toxic powder. Synonyms: barium monoxide, barium protoxide. · · Noun Definition 1 Synonyms · · · barium · · Synonym 1 ba · · Synonym 2 atomic number 56 · · Synonym 3 Characters · · space U+0020 a latin small letter a U+0061 b latin small letter b U+0062 d latin small letter d U+0064 e latin small letter e U+0065 i latin small letter i U+0069 m latin small letter m U+006D o latin small letter o U+006F r latin small letter r U+0072 u latin small letter u U+0075 x latin small letter x U+0078