: an elementary particle that is identical with the nucleus of the hydrogen atom, that along with the neutron is a constituent of all other atomic nuclei, that carries a positive charge numerically equal to the charge of an electron, and that has a mass of 1.673 × 10−27 kilogram
Examples of proton in a Sentence
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Since the 1990s, experiments have been looking for signs of WIMPs occasionally interacting with protons and neutrons via the weak force.
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Lyndie Chiou, Quanta Magazine, 7 May 2024
Over time, one of those extra neutrons will decay into a proton and produce a new electron.
—Rhett Allain, WIRED, 23 Feb. 2024
See all Example Sentences for proton 
Lyndie Chiou, Quanta Magazine, 7 May 2024
Over time, one of those extra neutrons will decay into a proton and produce a new electron.
—Rhett Allain, WIRED, 23 Feb. 2024
See all Example Sentences for proton
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'proton.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
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“Proton.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/proton. Accessed 29 May. 2024.
Copy CitationKids Definition
proton
noun
pro·ton
ˈprō-ˌtän 
: an atomic particle that occurs in the nucleus of every atom and carries a positive charge equal in size to the negative charge of an electron
Medical Definition
proton
noun
pro·ton
ˈprō-ˌtän
: an elementary particle that is identical with the nucleus of the hydrogen atom, that along with neutrons is a constituent of all other atomic nuclei, that carries a positive charge numerically equal to the charge of an electron, and that has a mass of 1.673×10−24 gram
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