cesium

n. (Cs) rare metallic element (Chemistry)

Caesium (also spelled cesium, IPA: ) is a chemical element in the periodic table that has the symbol Cs and atomic number 55. It is a soft silvery-gold alkali metal with a melting point of 28 °C (83 °F) which makes it one of the metals that are liquid at or near room temperature along with rubidium (39°C), francium (27 °C), mercury (-39 °C), and gallium (30 °C). This element is most notably used in atomic clocks.
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Noun
1. a soft silver-white ductile metallic element (liquid at normal temperatures); the most electropositive and alkaline metal
(synonym) caesium, Cs, atomic number 55
(hypernym) metallic element, metal
(hyponym) cesium 137
(substance-holonym) pollucite

n. caesium, soft metallic element (Chemistry)

n. (also: Cs) cesium, alkali metal element, univalent metal whith alkali hydroxides