rare earth element

noun

|Updated on: 15 Jun 2018

Definition of rare earth element

: any of a series of metallic elements of which the oxides are classed as rare earths and which include the elements of the lanthanide series and sometimes yttrium and scandium — called also rare earth metal

Recent Examples of rare earth element from the Web

Marine scientists at China’s Guangxi Key Laboratory recently deduced the strength of East Asian winter monsoons over the past 150 years by measuring levels of rare earth elements, such as lanthanum and cerium, in each layer of a Poritescoral core.

— elizabeth svoboda, Scientific American, "Cores from Coral Reefs Hold Secrets of the Seas’ Past and Future," 6 June 2018
Rare earth minerals contain rare earth elements (located here on the periodic table) that are used in high-tech devices like smartphones, missile systems, radar devices and hybrid vehicles.

— aj willingham, CNN, "How the mud in this small Japanese island could change the global economy," 16 Apr. 2018
Joshua Zide, an associate professor of materials science and engineering at the University of Delaware, studies rare earth elements, particularly terbium, which is part of the chemical element combination for Saini’s discovery.

— kristen a. schmitt, Smithsonian, "Is This New Material a Game Changer for Thermoelectricity?," 10 Apr. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rare earth element.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.