yttrium

American  

[i-tree-uhm] / ˈɪ tri əm /

noun

Chemistry.

1. a rare trivalent metallic element, found in gadolinite and other minerals. Y; 88.905; 39; 4.47.

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yttrium British  

/ ˈɪtrɪəm /

noun

1. a silvery metallic element occurring in monazite and gadolinite and used in various alloys, in lasers, and as a catalyst. Symbol: Y; atomic no: 39; atomic wt: 88.90585; valency: 3; relative density: 4.469; melting pt: 1522°C; boiling pt: 3338°C

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yttrium Scientific  

/ ĭt′rē-əm /

1. A silvery metallic element found in the same ores as elements of the lanthanide series. Yttrium is used to strengthen magnesium and aluminum alloys, to provide the red color in color televisions, and as a component of various optical and electronic devices. Atomic number 39; atomic weight 88.906; melting point 1,522°C; boiling point 3,338°C; specific gravity 4.45 (25°C); valence 3.

2. See Periodic Table

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Other Word Forms

• yttric adjective

Etymology

Origin of yttrium

1815–25; < New Latin, named after Ytterby. See ytterbia, -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

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

Heavy rare-earth elements include dysprosium, terbium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium.

From Barron's • Nov. 13, 2025

These include scandium, yttrium and the lanthanides, which account for 15 chemical elements in the periodic table.

From MarketWatch • Oct. 28, 2025

The Earth contains a great deal of iron and rather little yttrium.

From "Cosmos" by Carl Sagan