proton

noun

pro·​ton ˈprō-ˌtän How to pronounce proton (audio)
: 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
protonic adjective

Examples of proton in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Electrons gently tug on protons in the lattice, drawing them inward to create an excess of positive charge. Charlie Wood, Quanta Magazine, 6 Dec. 2024 They are created when protons and neutrons collide, which generates particles known as pions that then decay into muons. IEEE Spectrum, 3 Dec. 2024 That partnership will continue and expand with the proton therapy, Schultz said. Jessica Van Egeren, Journal Sentinel, 10 Nov. 2024 The medications do this by blocking the proton pump channel—a type of protein—in certain cells of the stomach wall. Ashley Wong, Health, 24 Sep. 2024 See all Example Sentences for proton 

Word History

Etymology

Greek prōton, neuter of prōtos first — more at proto-

First Known Use

1920, in the meaning defined above

Time Traveler
The first known use of proton was in 1920

Dictionary Entries Near proton

Cite this Entry

“Proton.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/proton. Accessed 21 Dec. 2024.

Kids Definition

proton

noun
pro·​ton ˈprō-ˌtän How to pronounce proton (audio)
: 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
protonic adjective

Medical Definition

proton

noun
pro·​ton ˈprō-ˌtän How to pronounce proton (audio)
: 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
protonic adjective

More from Merriam-Webster on proton

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