isotope

noun

iso·​tope ˈī-sə-ˌtōp How to pronounce isotope (audio)
1
: any of two or more species of atoms of a chemical element with the same atomic number and nearly identical chemical behavior but with differing atomic mass or mass number and different physical properties
2
isotopic adjective

Examples of isotope in a Sentence

Recent Examples on the Web Using a method called stable isotope analysis, which yields insights into an animal’s diet and environment, the team identified differences between the two sets of teeth that likely reflect how the region’s marine ecosystem has changed over the centuries, and how sharks have adapted. Sarah Sloat, Smithsonian Magazine, 29 Feb. 2024 Former Russian agent Alexander Litvinenko's poisoning with a radioactive isotope in London in 2006 is one example; the murder of journalist Jamal Khashoggi at a Saudi diplomatic facility in Istanbul in 2018 is another. Ryan Lucas, NPR, 25 Feb. 2024 But many questions remain on what other potentially more hazardous isotopes could’ve been dumped. Rosanna Xia, Los Angeles Times, 21 Feb. 2024 Getting to the meat of the matter, Zubrin makes a case for shipping deuterium–a rare isotope of hydrogen–from Mars to Earth based primarily on its 4x abundance there and the assumption that Starship will reduce interplanetary freight-costs to $100/kg. Greg Autry, Forbes, 20 Feb. 2024 Litvinenko, a former KGB spy who became a British intelligence agent and Putin critic, was soon hospitalized and found to have been poisoned with polonium-210, a radioactive isotope, that was in his green tea. Bryan Pietsch, Washington Post, 17 Feb. 2024 Researchers at the Alaska Stable Isotope Facility learned of Elma’s odyssey by analyzing isotopes from her tusk, which was first identified in 2009 at the Swan Point archaeological site in Interior Alaska. Jack Knudson, Discover Magazine, 17 Jan. 2024 Another promising enrichment technology, called laser enrichment, involves separating uranium isotopes based on the different energy levels at which their nuclei get excited. IEEE Spectrum, 13 Nov. 2023 But the researchers took things a step further with the Oak Ridge box turtle, looking at changes in uranium isotope concentrations across seven scute layers, marking the seven years of the turtle’s life between 1955 and 1962. Celia Ford, WIRED, 30 Aug. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'isotope.' 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

is- + Greek topos place

First Known Use

1913, in the meaning defined at sense 1

Time Traveler
The first known use of isotope was in 1913

Dictionary Entries Near isotope

Cite this Entry

“Isotope.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isotope. Accessed 19 Mar. 2024.

Kids Definition

isotope

noun
iso·​tope ˈī-sə-ˌtōp How to pronounce isotope (audio)
: any of the forms of an element that differ in the number of neutrons in an atom
isotopic adjective
isotopically adverb

Medical Definition

isotope

noun
iso·​tope ˈī-sə-ˌtōp How to pronounce isotope (audio)
1
: any of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table and nearly identical chemical behavior but with differing atomic mass or mass number and different physical properties
2
isotopic adjective
isotopically adverb
isotopy noun
plural isotopies

More from Merriam-Webster on isotope

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