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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.


isotope British  
/ ˌaɪsəˈtɒpɪk, ˈaɪsəˌtəʊp, aɪˈsɒtəpɪ /

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

isotope Scientific  
/ īsə-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.


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.


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. )

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Like Thanksgiving, but with isotopes and congressional hearings.

From MarketWatch

To understand daily life, researchers analyzed stable isotopes preserved in bones and teeth.

From Science Daily

The license specifically applies to Atomic Alchemy, a wholly-owned subsidiary dealing in the production of radioactive isotopes.

From Barron's

Oklo’s subsidiary, Atomic Alchemy, secured its first NRC license, allowing initial commercial sales of isotopes and a new revenue stream.

From Barron's

Oklo’s subsidiary, Atomic Alchemy, secures a NRC license to handle and distribute isotopes, enabling initial commercial sales.

From Barron's