isotope

American  

[ahy-suh-tohp] / ˈaɪ səˌtoʊp /

noun

Chemistry.

1. any of two or more forms of a chemical element, having the same number of protons in the nucleus, or the same atomic number, but having different numbers of neutrons in the nucleus, or different atomic weights. There are 275 isotopes of the 81 stable elements, in addition to over 800 radioactive isotopes, and every element has known isotopic forms. Isotopes of a single element possess almost identical properties.

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isotope British  

/ ˌaɪsəˈtɒpɪk, ˈaɪsəˌtəʊp, aɪˈsɒtəpɪ /

noun

1. one of two or more atoms with the same atomic number that contain different numbers of neutrons

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isotope Scientific  

/ ī′sə-tōp′ /

1. One of two or more atoms that have the same atomic number (the same number of protons) but a different number of neutrons. Carbon 12, the most common form of carbon, has six protons and six neutrons, whereas carbon 14 has six protons and eight neutrons. Isotopes of a given element typically behave alike chemically. With the exception of hydrogen, elements found on Earth generally have the same number of protons and neutrons; heavier and lighter isotopes (with more or fewer neutrons) are often unstable and undergo radioactive decay.

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isotope Cultural  

1. In physics, different forms of the same element, with nuclei that have the same number of protons but different numbers of neutrons. Isotopes are distinguished from each other by giving the combined number of protons and neutrons in the nucleus. For example, uranium 235 is the isotope of uranium that has 235 protons and neutrons in its nucleus rather than the more commonly occurring 238. All elements have isotopes.

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Other Word Forms

• isotopic adjective
• isotopically adverb
• isotopy noun

Etymology

Origin of isotope

First recorded in 1910–15; iso- + -tope, from Greek tópos “place”; Utopia ( def. )

Compare meaning

How does isotope compare to similar and commonly confused words? Explore the most common comparisons:

• isotope vs. isomer

Example Sentences

By comparing how much of each isotope was lost, researchers could estimate how much carbon dioxide participants produced and, in turn, how much energy they used.

From Science Daily

First-generation reactors will almost certainly be fueled by the hydrogen isotopes deuterium and tritium.

From The Wall Street Journal

Deuterium is a hydrogen isotope and has one more neutron.

From Science Daily

Strontium isotope ratios also pointed to a freshwater habitat.

From Science Daily

The Grenoble group analyzed strontium isotopes and trace elements in melt inclusions trapped inside 3.3-billion-year-old olivine crystals, providing rare geochemical snapshots of early Earth.

From Science Daily