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

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

In the U.S., rare earths—including neodymium, dysprosium, and praseodymium—are listed on the USGS’s critical minerals list for 2025.

From The Wall Street Journal • Jan. 23, 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

The rugged hills surrounding Ganzhou are home to the world's largest mining and processing operations of the strategic "heavy" elements, including dysprosium, yttrium and terbium.

From Barron's • Dec. 21, 2025

Shares in companies that aim to produce obscure minerals—including dysprosium, used in high-performance magnets, and magnesium, which strengthens aluminum alloys—rose by as much as 20% in Sydney on Tuesday after U.S.

From The Wall Street Journal • Oct. 21, 2025