radium

noun, often attributive
ra·​di·​um | \ ˈrā-dē-əm How to pronounce radium (audio) \

Definition of radium

: an intensely radioactive metallic chemical element that occurs in combination in minute quantities in minerals (such as pitchblende or carnotite), emits alpha particles and gamma rays to form radon, and is used chiefly in the treatment of cancer and in radiographic devices — see Chemical Elements Table

Examples of radium in a Sentence

Recent Examples on the Web The city must reach the halfway point of completion by spring 2022 or it would be forced to install temporary radium-removal equipment, at a price previously estimated at $5 million by utility officials. Jim Riccioli, Milwaukee Journal Sentinel, "Squabble over Lake Michigan water plan could cost Waukesha millions of dollars in delays," 23 Dec. 2019 The two discovered two radioactive elements together: polonium and radium. Georgia Slater, PEOPLE.com, "#SeeHer Story Honors Marie and Irène Curie, Mother-Daughter Medicine Moguls in Episode 11," 18 Dec. 2019 Clark said there are many, many paths uranium and radium can travel that poison lands, waters and living things. Debra Krol, azcentral, "House to vote on permanently banning uranium mines near the Grand Canyon," 29 Oct. 2019 The first insert is set in Cleveland in 1957, where a doctor tests a new radium gun on a young boy suffering from cancer. Deborah Young, The Hollywood Reporter, "'Radioactive': Film Review | TIFF 2019," 6 Sep. 2019 Scientists knew that exposing atoms to a radioactive element like radium would trigger reactions, revealing details of their internal structure and physics. New York Times, "Overlooked No More: Elizabeth Rona, Pioneering Scientist Amid Dangers of War," 28 Aug. 2019 Furthermore, private entrepreneurs are beginning to commercialize radium in everything from toothpaste to face cream. Deborah Young, The Hollywood Reporter, "'Radioactive': Film Review | TIFF 2019," 6 Sep. 2019 But radium was rare and costly, with tiny quantities hoarded and chivvied between nations for experiments. New York Times, "Overlooked No More: Elizabeth Rona, Pioneering Scientist Amid Dangers of War," 28 Aug. 2019 Of course, tobacco eventually joined the list of treacherous substances once thought to be healthy and subsequently discovered to be harmful, keeping excellent company alongside radium and mercury. Cathleen O'grady, Ars Technica, "What do we actually know about the risks of screen time and digital media?," 17 Oct. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'radium.' 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 radium

1899, in the meaning defined above

History and Etymology for radium

New Latin, from Latin radius ray

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Time Traveler for radium

Time Traveler

The first known use of radium was in 1899

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Statistics for radium

Last Updated

26 Dec 2019

Cite this Entry

“Radium.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/radium. Accessed 21 January 2020.

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More Definitions for radium

radium

noun
How to pronounce radium (audio)

English Language Learners Definition of radium

: a radioactive element that is used medically in cancer treatments

radium

noun
ra·​di·​um | \ ˈrā-dē-əm How to pronounce radium (audio) \

Kids Definition of radium

: a strongly radioactive element found in very small quantities in various minerals (as pitchblende) and used in the treatment of cancer

radium

noun, often attributive
ra·​di·​um | \ ˈrād-ē-əm How to pronounce radium (audio) \

Medical Definition of radium

: an intensely radioactive shining white metallic element that resembles barium chemically, that occurs in combination in minute quantities in minerals (as pitchblende or carnotite) principally as the isotope of mass number 226 formed from uranium 238, having a half-life of 1620 years, and emitting alpha particles and gamma rays to form radon, and that is used chiefly in luminous materials and in the treatment of cancer symbol Ra — see Chemical Elements Table

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More from Merriam-Webster on radium

Rhyming Dictionary: Words that rhyme with radium

Spanish Central: Translation of radium

Nglish: Translation of radium for Spanish Speakers

Britannica.com: Encyclopedia article about radium

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