terbium

American  

[tur-bee-uhm] / ˈtɜr bi əm /

noun

Chemistry.

1. a rare-earth, metallic element present in certain minerals and yielding colorless salts. Tb; 65; 158.924; 8.25.

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terbium British  

/ ˈtɜːbɪəm /

noun

1. a soft malleable silvery-grey element of the lanthanide series of metals, occurring in gadolinite and monazite and used in lasers and for doping solid-state devices. Symbol: Tb; atomic no: 65; atomic wt: 158.92534; valency: 3 or 4; relative density: 8.230; melting pt: 1356°C; boiling pt: 3230°C

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terbium Scientific  

/ tûr′bē-əm /

1. A soft, silvery-gray metallic element of the lanthanide series. It is used in color television tubes, x-ray machines, and lasers. Atomic number 65; atomic weight 158.925; melting point 1,356°C; boiling point 3,123°C; specific gravity 8.229; valence 3, 4.

2. See Periodic Table

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Other Word Forms

Derived Forms

• terbic
  adjective

Etymology

Origin of terbium

1835–45; (Yt)terb(y) , name of Swedish town where found + -ium. See ytterbium

Example Sentences

Northern Minerals owns the Browns Range project in Western Australia, a potential source of heavy rare earths dysprosium and terbium that are today mostly produced by China.

From The Wall Street Journal • May 19, 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

Visited this month by AFP, the southeastern mining region of Ganzhou -- which specialises in "heavy" rare earths including yttrium and terbium -- was a hive of activity.

From Barron's • Nov. 26, 2025

Rare earths, like samarium and terbium, are critical to the production of technologies set to shape the world in the coming decades – including electric vehicles and highly advanced weapons systems.

From BBC • Apr. 25, 2025

Er�bium, a rare metal found along with yttrium, terbium, and other rare elements in some rare minerals.

From The New Gresham Encyclopedia Volume 4, Part 2: Ebert to Estremadura by Various