beryllium

American  

[buh-ril-ee-uhm] / bəˈrɪl i əm /

noun

Chemistry.

1. a steel-gray, bivalent, hard, light, metallic element, the salts of which are sweet: used chiefly in copper alloys for better fatigue endurance, in springs, and in electrical contacts. Be; 9.0122; 4; 1.8 at 20° C.

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beryllium British  

/ bɛˈrɪlɪəm /

noun

1. Former names: glucinum.   glucinium.  a corrosion-resistant toxic silvery-white metallic element that occurs chiefly in beryl and is used mainly in X-ray windows and in the manufacture of alloys. Symbol: Be; atomic no: 4; atomic wt: 9.012; valency: 2; relative density: 1.848; melting pt: 1289°C; boiling pt: 2472°C

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beryllium Scientific  

/ bə-rĭl′ē-əm /

1. A hard, lightweight, steel-gray metallic element of the alkaline-earth group, found in various minerals, especially beryl. It has a high melting point and is corrosion-resistant. Beryllium is used to make sturdy, lightweight alloys and aerospace structural materials. It is also used as a neutron moderator in nuclear reactors. Atomic number 4; atomic weight 9.0122; melting point 1,278°C; boiling point 2,970°C; specific gravity 1.848; valence 2.

2. See Periodic Table

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Etymology

Origin of beryllium

1860–65; < Latin bēryll ( us ) beryl + -ium

Example Sentences

To generate the required beam, scientists accelerated Mo-92 ions and fired them at a beryllium target, producing fast moving Mo-86 nuclei.

From Science Daily • Mar. 8, 2026

McCanlies was studying how a toxic chemical, beryllium, causes chronic lung inflammation in workers when she began to think seriously about autism.

From Salon • Aug. 21, 2025

Though there haven’t been many studies on beryllium exposure, those that have been done suggest that it may raise the risk of lung cancer.

From Los Angeles Times • May 4, 2025

Other elements found in Ukraine include beryllium and uranium, which are both crucial for nuclear weapons and reactors.

From BBC • Apr. 30, 2025

For light elements like lithium and beryllium, the high yield was not particularly surprising, but the same thing happened with heavier atoms like gold and platinum.

From "Big Science" by Michael Hiltzik