Word Study
rubidium
WORDNET DICTIONARY
Noun rubidium has 1 sense
- rubidium(n = noun.substance) atomic number 37, rb - 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; Array is a kind of metal, metallic element
CIDE DICTIONARY
rubidium, n. [NL., fr. L. rubidus red, fr. rubere to be red. So called from two dark red spectroscopic lines by means of which it was discovered in the lepidolite from Rozena, Moravia. See Rubicund.].
A rare metallic element of the alkali metal series, atomic number 37. It occurs quite widely, but in small quantities, and always combined. It is isolated as a soft yellowish white metal, analogous to potassium in most of its properties. Symbol Rb. Atomic weight, 85.48. [1913 Webster]
OXFORD DICTIONARY
rubidium, n. Chem. a soft silvery element occurring naturally in various minerals and as the radioactive isotope rubidium-87.
Usage
Symb.: Rb.
Etymology
L rubidus red (with ref. to its spectral lines)
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