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

Smaller quantities of other separated heavy rare earth oxides like dysprosium, terbium and samarium are sold in 25-kilogramme tins.

From Barron's • Apr. 22, 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

Samsara Eco plans to focus initially on rare earths such as neodymium and dysprosium, which are used as alloys in magnets.

From The Wall Street Journal • Mar. 10, 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