dysprosium

American  

[dis-proh-see-uhm, -shee-] / dɪsˈproʊ si əm, -ʃi- /

noun

Chemistry.

1. a rare-earth metallic element, highly reactive and paramagnetic, found in small amounts in various rare-earth minerals, as euxenite and monazite: used to absorb neutrons in nuclear reactors. Dy; 162.50; 66.

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dysprosium British  

/ dɪsˈprəʊsɪəm /

noun

1. a soft silvery-white metallic element of the lanthanide series: used in laser materials and as a neutron absorber in nuclear control rods. Symbol: Dy; atomic no: 66; atomic wt: 162.50; valency: 3; relative density: 8.551; melting pt: 1412°C; boiling pt: 2567°C

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dysprosium Scientific  

/ dĭs-prō′zē-əm /

1. A soft, silvery metallic element of the lanthanide series. Because it has a high melting point and absorbs neutrons well, dysprosium is used to help control nuclear reactions. Atomic number 66; atomic weight 162.50; melting point 1,407°C; boiling point 2,600°C; specific gravity 8.536; valence 3.

2. See Periodic Table

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Etymology

Origin of dysprosium

1885–90; < New Latin < Greek dysprós ( itos ) hard to get at ( dys- dys- + pros- to + itós, past participle of iénai to go) + -ium

Example Sentences

The solution is to add a dose of “heavy” rare earths, which have names like dysprosium and terbium and which allow the magnet to keep working when it gets hot.

From The Wall Street Journal • Jun. 2, 2026

The deposit includes yttrium and dysprosium used in permanent magnets, clean-energy technologies, and advanced chemicals.

From Barron's • May 20, 2026

Geological Survey geologists first identified rare earth mineralization in the Music Valley area in 1954, with sampling reporting enrichment in dysprosium, terbium, yttrium and ytterbium, Dateline Resources said in a press release.

From Los Angeles Times • Mar. 30, 2026

Valor has designed reusable ligands for 10 elements, including gold, copper, platinum, nickel and a number of otherwise difficult-to-isolate rare earths, including cerium, dysprosium and yttrium.

From The Wall Street Journal • Mar. 11, 2026

So, it has surpluses of lighter rare earths such as neodymium, but lacks extractable quantities of heavier elements like dysprosium and terbium, which are critical for many high-performance magnets.

From BBC • Jan. 15, 2026