cerium (n.) Look up cerium at Dictionary.com
element, first isolated in pure form in 1875, named for ceria, the name of the earth from which it was taken, which was discovered in 1803 and named by Berzelius and Hissinger for Ceres, the minor planet, which had been discovered in 1801 and named for the Roman goddess Ceres. With metallic element ending -ium.