lanthanide

American  

[lan-thuh-nahyd, -nid] / ˈlæn θəˌnaɪd, -nɪd /

noun

Chemistry.

1. any element of the lanthanide series.

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lanthanide British  

/ ˈlænθəˌnaɪd, ˈlænθəˌnɒn /

noun

1. Also called: rare earth.   rare-earth element.  any element of the lanthanide series

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lanthanide Scientific  

/ lăn′thə-nīd′ /

1. Any of a series of 15 naturally occurring metallic elements. The lanthanides include elements having atomic numbers 57 (lanthanum) through 71 (lutetium). They are grouped apart from the rest of the elements in the Periodic Table because they all behave in a similar way in chemical reactions.

2. Also called rare-earth element

3. See Periodic Table

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Etymology

Origin of lanthanide

First recorded in 1925–30; lanthan(um) + -ide ( def. )

Example Sentences

With important electrical and magnetic qualities, rare earths consist of 17 elements in the lanthanide group of the periodic table, plus scandium and yytrium.

From BBC • Feb. 5, 2026

In this design, however, the energy from the triplet state is transferred with more than 98% efficiency to the lanthanide ions inside the insulating nanoparticles, causing them to emit light with remarkable brightness.

From Science Daily • Dec. 5, 2025

Notably, the team provided the first demonstration of a feature of lanthanide contraction in solution for the whole lanthanide series, including promethium, atomic number 61.

From Science Daily • May 22, 2024

In a statement on Tuesday, Lynas said the change to its licence will allow its Malaysian facility to continue to import and process lanthanide concentrate from its mine in Western Australia.

From Reuters • Oct. 25, 2023

Because lanthanum behaves very much like the lanthanide elements, it is considered a lanthanide element, even though its electron configuration makes it the first member of the third transition series.

From Textbooks • Feb. 14, 2019