radium

noun

ra·​di·​um ˈrā-dē-əm How to pronounce radium (audio)
often attributive
: 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 Both radium and radon are radioactive and can cause cancer. Shawn Tully, Fortune, 9 Oct. 2024 The hands and indexes are delicately filled with egg-shell colored Super-LumiNova, reflecting the radium originally used, ensuring visibility in all lighting conditions. Bhanu Chopra, Forbes, 3 Sep. 2024 It’s inferred that this strange symbol is indicative of a radium dial that conforms to Atomic Energy Commission guidelines from 1960, and that uses less radioactive material than earlier 1950s-era timepieces. Oren Hartov, Robb Report, 4 July 2024 This byproduct of burning coal to generate power is full of heavy metals and toxic elements such as arsenic, mercury, chromium and even radium. Sarah Bowman, The Indianapolis Star, 20 Feb. 2024 See all Example Sentences for radium 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'radium.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

New Latin, from Latin radius ray

First Known Use

1898, in the meaning defined above

Time Traveler
The first known use of radium was in 1898

Dictionary Entries Near radium

Cite this Entry

“Radium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radium. Accessed 5 Nov. 2024.

Kids Definition

radium

noun
ra·​di·​um ˈrād-ē-əm How to pronounce radium (audio)
: a strongly radioactive shining white metallic element that is chemically similar to barium, occurs in combination in very small quantities in minerals (as pitchblende), and is used in the treatment of cancer see element

Medical Definition

radium

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