noun Etymology: New Latin, from Latin rubidus red, from rubēre Date: 1861 a soft silvery metallic element of the alkali metal group that reacts violently with water and bursts into flame spontaneously in air
RUBIDIUM
Meaning of RUBIDIUM in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012