Noun Concept
Categories: Articles with short description, Sets of chemical elements, long volume value, Lanthanides, Periodic table
lanthanide  lanthanoid  rare-earth element  lanthanon  rare earth
The rare-earth elements, also called the rare-earth metals or rare-earth oxides, or the lanthanides are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals. Wikipedia
The lanthanide or lanthanoid series of chemical elements comprises the 15 metallic chemical elements with atomic numbers 57–71, from lanthanum through lutetium. Wikipedia
Trivalent metallic rare earth elements Wikidata
Any of the fifteen lanthanides plus scandium and yttrium Wikidata
Any of the 15 chemical elements from lanthanum (atomic number 57) to lutetium (atomic number 71) with very similar chemistry. OmegaWiki
Any of the 14 rare earth elements from cerium (or from lanthanum) to lutetium in the periodic table; because their outermost orbitals are empty, they have very similar chemistry; below them are the actinides. Wiktionary
Any of the 14 rare earth elements. Wiktionary (translation)
Lanthanide. Wiktionary
Any of a group of seventeen soft, lustrous, sometimes magnetic metals that form trivalent salts; they include the lanthanides plus yttrium, scandium, thorium and sometimes zirconium. Wiktionary
Type of metal. Wiktionary (translation)
Rare earth element. Wiktionary