polonium

American  

[puh-loh-nee-uhm] / pəˈloʊ ni əm /

noun

Chemistry.

1. a radioactive element discovered by Pierre and Marie Curie in 1898; Po; 84; about 210.

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polonium British  

/ pəˈləʊnɪəm /

noun

1. a very rare radioactive element that occurs in trace amounts in uranium ores. The isotope polonium-210 is produced artificially and is used as a lightweight power source in satellites and to eliminate static electricity in certain industries. Symbol: Po; atomic no: 84; half-life of most stable isotope, ²⁰⁹ Po: 103 years; valency: –2, 0, 2, 4, or 6; relative density (alpha modification): 9.32; melting pt: 254°C; boiling pt: 962°C

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polonium Scientific  

/ pə-lō′nē-əm /

1. A very rare, naturally radioactive, silvery-gray or black metalloid element. It is produced in extremely small amounts by the radioactive decay of radium or the bombardment of bismuth or lead with neutrons. Atomic number 84; melting point 254°C; boiling point 962°C; specific gravity 9.20; valence 2, 4.

2. See Periodic Table

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Etymology

Origin of polonium

1895–1900; < New Latin, equivalent to polon- (< Medieval Latin Polonia Poland) + -ium -ium

Example Sentences

This surprising finding led to the discovery of polonium and radium and helped establish the field of nuclear physics and chemistry.

From Science Daily • Mar. 14, 2026

Curie used the building for some of her pioneering work on radioactivity and later became the first woman to win a Nobel Prize, for discovering polonium and radium.

From Science Magazine • Jan. 10, 2024

It also found high levels of polonium, radium and other material in various places throughout the school.

From Seattle Times • Oct. 18, 2022

The report found significant levels of radioactive isotope lead-210, polonium, radium and other toxins when researchers took samples from the school in August, according to the St. Louis Dispatch.

From Washington Times • Oct. 17, 2022

Their method involved bombarding aluminum foils with alpha rays produced by their usual rudimentary source, a hunk of the inexpensive but vigorous alpha emitter polonium.

From "Big Science" by Michael Hiltzik