- any of a group of closely related metallic elements, comprising the lanthanides, scandium, and yttrium, that are chemically similar by virtue of having the same number of valence electrons.
Origin of rare-earth element
First recorded in 1955–60
Also called rare-earth metal.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Related Words for rare-earth elementoxide
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- See lanthanide.
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