rubidium
Syllabification: (ru·bid·i·um)
Pronunciation: /ro͞oˈbidēəm/
Definition of rubidium
noun
Origin:
mid 19th century: modern Latin, from Latin rubidus 'red' (with reference to its spectral lines)
mid 19th century: modern Latin, from Latin rubidus 'red' (with reference to its spectral lines)