Cerium
noun ·Uncommon ·Advanced level
Definitions
- 1 A chemical element (symbol Ce) with an atomic number of 58, a very soft, ductile, silvery-white metal that tarnishes when exposed to air. uncountable, usually
"Despite their name, rare earths are not so rare. The most common, cerium, is as plentiful in the Earth's crust as copper or lead. The difference between them and more familiar materials is that, in nature, rare earths are almost never found on their own. Rather, they're mixed with other minerals, and often at low concentrations, making them difficult to mine economically."
- 2 a ductile grey metallic element of the lanthanide series; used in lighter flints; the most abundant of the rare-earth group wordnet
Example
More examples"Despite their name, rare earths are not so rare. The most common, cerium, is as plentiful in the Earth's crust as copper or lead. The difference between them and more familiar materials is that, in nature, rare earths are almost never found on their own. Rather, they're mixed with other minerals, and often at low concentrations, making them difficult to mine economically."
Etymology
From Ceres (“a recently discovered asteroid”) + -ium.
Related phrases
More for "cerium"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.