The name is derived from an Ancient Greek word meanin "to lie hidden", because it was hard to find and isolate this element. It is the eponym of a whole group of elements: the lanthanides.
The Name neodymium means "new twin" (from the Greek words neo = new and didymos = twin), because it is quite similar to lanthanum. It is famous for strong magnets, which are made of an alloy of neodymium, iron and boron.
Thulium was named after the ancient mythical place called Thule, which stands for either Scandinavia or an island in the North Atlantic – depending upon interpretation.
The element cerium was named after the dwarf planet Ceres, which itself was named after the Roman goddess of agriculture and fertility. Even though it belongs to the rare earth elements, it is not so rare on earth. It is even more abundant than tin or lead – just not in its pure form but always in compounds. It is used for example in lighter flints.
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