isotope
noun
iso·tope
ˈī-sə-ˌtōp 
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
: nuclide
Examples of isotope in a Sentence
Recent Examples on the Web
Carol Sutton Lewis: In the late fifties, scientists at the Atomic Energy Commission were finding new information about a radioactive isotope called Strontium 90.
—
Carol Sutton Lewis, Scientific American, 18 June 2025
The site in question, Iran's mysterious Fordow Fuel Enrichment Plant, is built into a mountainside and seems to be in the business of processing uranium isotopes.
—Geoff Brumfiel, NPR, 18 June 2025
Genetic testing was just becoming possible on a large scale, and there were other types of new tests being developed that use isotopes and other things to date paleontological remains.
—Ari Daniel, Smithsonian Magazine, 12 June 2025
Dental, anthropological and isotope analyses were conducted.
—June 4, CBS News, 4 June 2025
See All Example Sentences for isotope
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Carol Sutton Lewis, Scientific American, 18 June 2025
The site in question, Iran's mysterious Fordow Fuel Enrichment Plant, is built into a mountainside and seems to be in the business of processing uranium isotopes.
—Geoff Brumfiel, NPR, 18 June 2025
Genetic testing was just becoming possible on a large scale, and there were other types of new tests being developed that use isotopes and other things to date paleontological remains.
—Ari Daniel, Smithsonian Magazine, 12 June 2025
Dental, anthropological and isotope analyses were conducted.
—June 4, CBS News, 4 June 2025
See All Example Sentences for isotope
Cite this Entry
“Isotope.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isotope. Accessed 28 Jun. 2025.
Copy CitationKids Definition
isotope
noun
iso·tope
ˈī-sə-ˌtōp
: any of the forms of an element that differ in the number of neutrons in an atom
Medical Definition
isotope
noun
iso·tope
ˈī-sə-ˌtōp
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
: nuclide
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