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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
What the Dutch scientists did was to look at the ratios of ruthenium and tungsten isotopes found in oceanic basalts and picrites from Hawaii, Baffin Island, Galápagos, and La Réunion islands. David Szondy june 07, New Atlas, 7 June 2025 An international team of researchers reached this conclusion after analyzing the ratio of different variants, called isotopes, of the mineral zinc in 18-million-year-old megalodon teeth. Margherita Bassi, Smithsonian Magazine, 29 May 2025 McCormack said that the new method of determining tooth zinc isotope ratios has once proven to be a valuable instrument for paleoecological reconstructions. Maria Azzurra Volpe, MSNBC Newsweek, 26 May 2025 The particles coming from the sun collide with gases in Earth’s atmosphere, forming new isotopes like the radioactive beryllium-10 and carbon-14 (or radiocarbon). David Bressan, Forbes.com, 25 May 2025 See All Example Sentences for isotope

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

Browse Nearby Words

Cite this Entry

“Isotope.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isotope. Accessed 11 Jun. 2025.

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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