1
: a proton or neutron especially in the atomic nucleus
2
: a hypothetical single entity with one-half unit of isospin that can manifest itself as either a proton or a neutron

Examples of nucleon in a Sentence

Recent Examples on the Web
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It’s made up of a central nucleus consisting of protons and neutrons, called nucleons, with electrons orbiting around the nucleus. Artemis Spyrou, Discover Magazine, 9 Oct. 2024 This residual intranuclear binding force is much weaker than the strong force inside the nucleon. Aaron Shattuck, Scientific American, 17 Sep. 2024

Word History

Etymology

International Scientific Vocabulary

First Known Use

1923, in the meaning defined at sense 1

Time Traveler
The first known use of nucleon was in 1923

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Cite this Entry

“Nucleon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nucleon. Accessed 10 Mar. 2025.

Medical Definition

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