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
Oritain’s proprietary forensic origin verification methodology uses multiple analytical techniques, including isotopes, trace elements and non-traditional isotopes, along with statistical modeling through a global reference database to ensure supply chain transparency.
—
Angela Velasquez, Footwear News, 27 Apr. 2026
In fact, the zone is expected to persist for millennia, mainly because of radioactive isotopes, such as plutonium-bearing fuel particles with a half-life of 24,000 years.
—Georgina Jedikovska, Interesting Engineering, 26 Apr. 2026
The Level 5 accident dumped radioactive contamination across Europe and it is thought that traces of isotope iodine-131 may have caused several hundred cancer diagnoses.
—Kurt Snibbe, Oc Register, 25 Apr. 2026
But for the weightier version, at least one of those hydrogen atoms is a heavier isotope such as deuterium—which, unlike a typical hydrogen atom, has one neutron.
—Joseph Howlett, Scientific American, 24 Apr. 2026
See All Example Sentences for isotope
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Angela Velasquez, Footwear News, 27 Apr. 2026
In fact, the zone is expected to persist for millennia, mainly because of radioactive isotopes, such as plutonium-bearing fuel particles with a half-life of 24,000 years.
—Georgina Jedikovska, Interesting Engineering, 26 Apr. 2026
The Level 5 accident dumped radioactive contamination across Europe and it is thought that traces of isotope iodine-131 may have caused several hundred cancer diagnoses.
—Kurt Snibbe, Oc Register, 25 Apr. 2026
But for the weightier version, at least one of those hydrogen atoms is a heavier isotope such as deuterium—which, unlike a typical hydrogen atom, has one neutron.
—Joseph Howlett, Scientific American, 24 Apr. 2026
See All Example Sentences for isotope
Cite this Entry
“Isotope.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isotope. Accessed 29 Apr. 2026.
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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