be·​ryl·​li·​um | \ bə-ˈri-lē-əm How to pronounce beryllium (audio) \

Definition of beryllium

: a chemical element of the alkaline earth metal group with atomic number 4 that occurs naturally in minerals such as beryl and is steel-gray in color, light and strong but brittle, and is used chiefly as a hardening agent in alloys — see Chemical Elements Table

Examples of beryllium in a Sentence

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Argon can be measured from the lava flows as the radioactive decay of potassium occurs in the rocks, while beryllium can be measured in the ice cores. Ashley Strickland, CNN, "Earth's roaming magnetic poles create longer periods of instability, study says," 7 Aug. 2019 Gary Sexton, a former chemical operator, has trouble breathing due to the beryllium levels at the plant, the lawsuit said. Sarah Brookbank,, "Lawsuit: Residents near Portsmouth Gaseous Diffusion Plant have been 'sacrificial lambs'," 30 June 2019 Another gauge of erosion comes from a set of isotopes—of helium, beryllium, and aluminum—that form when cosmic rays bombard surface rocks. Paul Voosen, Science | AAAS, "Dinosaur-age landscapes lurk in Southern Hemisphere," 26 June 2019 Hoyle state nuclei almost always decay right back into beryllium and an alpha particle. Quanta Magazine, "A Primordial Nucleus Behind the Elements of Life," 4 Dec. 2012 The MW07s have high-end materials in their construction, including stainless steel enclosures, 10mm beryllium drivers, and acetate covers. Stefan Etienne, The Verge, "Master & Dynamic MW07 earbuds review: truly wireless, truly expensive," 18 Sep. 2018 Master & Dynamic has made that possible with the MW50+ headphones that retail for $399 — these are premium cans with 40mm beryllium drivers, after all. Stefan Etienne, The Verge, "Master & Dynamic MW50+ review: weak magnetism," 5 July 2018 Soils below those levels are placed in other stockpiles, and further tested for beryllium and lead levels. Keith Matheny, Detroit Free Press, "Radioactive soil from Ohio heads to Wayne County landfill next week," 22 June 2018 In addition to beryllium, the soil contains lead and radioactive elements of thorium, radium and uranium. Keith Matheny, Detroit Free Press, "Radioactive soil from Ohio heads to Wayne County landfill next week," 22 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'beryllium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of beryllium

circa 1847, in the meaning defined above

History and Etymology for beryllium

New Latin, from Greek bēryllion

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The first known use of beryllium was circa 1847

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be·​ryl·​li·​um | \ bə-ˈril-ē-əm How to pronounce beryllium (audio) \

Medical Definition of beryllium

: a steel-gray light strong brittle toxic bivalent metallic element used chiefly as a hardening agent in alloys symbol Be — see Chemical Elements Table

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