: 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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Read for yourself: Andromeda stepped back in terror, only to feel her proton backplate meet the cold, unforgiving steel of the mainframe’s terminus.
—
Sean McGowan, The New Yorker, 19 June 2024
These would have been even smaller — just the mass of a rhino, condensed into less than the volume of a single proton.
—Jacopo Prisco, CNN, 17 June 2024
Occasionally, heavy atomic nuclei spontaneously—and for no good reason—transform themselves, with either a neutron converting into a proton or vice-versa.
—Paul Sutter, Ars Technica, 11 June 2024
To make element 118, oganesson, scientists beam calcium at californium (98 protons).
—Stephanie Pappas, Scientific American, 14 May 2024
See all Example Sentences for proton 
Sean McGowan, The New Yorker, 19 June 2024
These would have been even smaller — just the mass of a rhino, condensed into less than the volume of a single proton.
—Jacopo Prisco, CNN, 17 June 2024
Occasionally, heavy atomic nuclei spontaneously—and for no good reason—transform themselves, with either a neutron converting into a proton or vice-versa.
—Paul Sutter, Ars Technica, 11 June 2024
To make element 118, oganesson, scientists beam calcium at californium (98 protons).
—Stephanie Pappas, Scientific American, 14 May 2024
See all Example Sentences for proton
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“Proton.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/proton. Accessed 30 Jun. 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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