ra·​di·​ol·​y·​sis ˌrā-dē-ˈä-lə-səs How to pronounce radiolysis (audio)
: chemical decomposition by the action of radiation
radiolytic adjective

Example Sentences

Recent Examples on the Web Cassini's data show that molecular oxygen (O2) forms inside the moon's surface ice when water molecules (H2O) are split by energetic ions, a process known as radiolysis. Andrew Moseman, Discover Magazine, 29 Nov. 2010 One example is radiolysis, in which subatomic particles naturally emitted by radioactive rocks such as granite cause certain molecules to break apart, releasing hydrogen. WIRED, 24 Nov. 2022 Now a study published in Astrobiology contends that radiolysis could have powered microbial life in the Martian subsurface. Nikk Ogasa, Scientific American, 19 July 2021 Scientists have previously studied Mars radiolysis, but this marks the first estimate using Martian rocks to quantify the planet’s subsurface habitability. Nikk Ogasa, Scientific American, 19 July 2021 Sherwood Lollar, Lin, Onstott and their collaborators proposed in 2006 that the microbial communities under South Africa and Canada derived the energy for their survival from hydrogen produced through radiolysis. Quanta Magazine, 31 May 2021 That process, water radiolysis, was first observed in Marie Curie’s laboratory at the beginning of the 20th century, when researchers realized that solutions of radium salts generated bubbles of hydrogen and oxygen. Quanta Magazine, 31 May 2021 So began their long quest to unpack how important radiolysis might be to life in natural settings. Quanta Magazine, 31 May 2021 Radiolysis could also help create food for these aliens. Margi Murphy, Fox News, 24 May 2017 See More

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

Word History


New Latin

First Known Use

1948, in the meaning defined above

Time Traveler
The first known use of radiolysis was in 1948

Dictionary Entries Near radiolysis

Cite this Entry

“Radiolysis.” Dictionary, Merriam-Webster, Accessed 9 Jun. 2023.

Medical Definition


ra·​di·​ol·​y·​sis ˌrād-ē-ˈäl-ə-səs How to pronounce radiolysis (audio)
plural radiolyses -ˌsēz How to pronounce radiolysis (audio)
: chemical decomposition by the action of radiation compare photolysis

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