cesium

ce si um |ˈsēzēəm ˌsiziəm |(Brit. caesium ) ▶noun the chemical element of atomic number 55, a soft, silvery, extremely reactive metal. It belongs to the alkali metal group and occurs as a trace element in some rocks and minerals. (Symbol: Cs ) ORIGIN mid 19th cent.: from Latin caesius ‘grayish-blue ’ (because it has characteristic lines in the blue part of the spectrum ).

cesium

ces ¦ium ▶noun US spelling of caesium.

cesium

ce si um ｟英 ｠cae si um /síːziəm /名詞 U 〘化 〙セシウム 〘金属元素; ｟記号 ｠ Cs 〙.