Definition of isotope
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
isotopicplay \ˌī-sə-ˈtä-pik, -ˈtō-\ adjective
isotopicallyplay \ˌī-sə-ˈtä-pi-k(ə-)lē, -ˈtō-\ adverb
Recent Examples of isotope from the Web
But this rocket is temperamental, and as unstable as a radioactive isotope.
Hobbie notes that people can be carbon-dated, thanks to radiocarbon isotopes in tooth enamel and other human tissues put together after the thermonuclear tests of the mid-20th century.
Elements come in a variety of flavors, known as isotopes; for instance, there’s regular old oxygen, or 16O, which has eight neutrons and eight protons, but also the rare 17O, which has an extra neutron.
Scientists estimate that the moon holds ____________ metric tons of the rare isotope helium-3, and 40 tons could power the U.S. for a year.
The 60 million-year-old flood basalts of Baffin Bay, Greenland, sampled by the geochemist Hanika Rizo (center) and colleagues, contain isotope traces that originated more than 4.5 billion years ago.
But the subtle anomalies in tungsten and other isotope concentrations are now providing the first glimpses of the planet’s formation and differentiation.
This and other isotope concentrations in the rocks suggest the hypothetical plumes that produced them might draw from a primordial pocket of metals, including tungsten-184.
To help measure bone calcium, the women were given orally a minute amount of a radioactive calcium isotope that was gradually incorporated into the skeleton.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'isotope'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of isotope
is- + Greek topos place
First Known Use: 1913
ISOTOPE Defined for English Language Learners
Definition of isotope for English Language Learners
chemistry : any one of various forms in which the atoms of a chemical element can occur
Medical Definition of isotope
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
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