8 letters · 13 points in Scrabble
noun a soft silvery metallic element of the alkali metal group; burns in air and reacts violently in water; occurs in carnallite and lepidolite and pollucite
originA New Latin word derived by German chemist R. W. Bunsen in 1861, from Latin rūbidus (“red”) because its spectrum has two red lines.
Etymology from Wiktionary, CC BY-SA 3.0