rare-earth element

Definitions of rare-earth element

1. noun

   any of the metallic elements of the lanthanide series (atomic numbers 57 through 71), along with scandium (atomic number 21) and yttrium (atomic number 39)
   synonyms: lanthanide, lanthanoid, lanthanon, rare earth

   types:

   terbium metal

   a separate group of related lanthanides, including terbium, europium, gadolinium, and sometimes dysprosium

   type of:

   group, grouping

   any number of entities (members) considered as a unit