proton

noun
pro·​ton | \ ˈprō-ˌtän \

Definition of proton

: 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

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Other Words from proton

protonic \ prō-​ˈtä-​nik \ adjective

Examples of proton in a Sentence

Recent Examples on the Web

Perhaps there could even be a kernel inside the shell of neutrons and protons with that elusive negative mass required to power something like the Alcubierre warp drive. Jennifer Ouellette, Ars Technica, "The Orville blends science fiction and science fact into a winning mix," 29 Dec. 2018 Scientists discovered in 1912 that subatomic particles — the building blocks of matter, such as protons, electrons, muons, neutrinos, and quarks — hit the Earth every day. Brian Resnick, Vox, "10 science stories in 2018 that made us go, “Whoa, that’s awesome”," 18 Dec. 2018 Each atom of the stuff packs a whopping 118 protons into its dense center. Michael Block, Scientific American, "The Quest for Superheavy Elements and the Island of Stability," 19 Mar. 2018 On the other hand, proton beam therapy can treat just the targeted area. The Seattle Times, "Protecting this mom’s heart from radiation," 15 Oct. 2018 Future research can examine universes with different strengths of the strong nuclear force, the strongest known force between particles, which binds protons together in atomic nuclei, despite their mutual repulsion, Howe said. Charles Q. Choi, Space.com, "Why Alternate Universes Might Also Host Life Around their Stars," 26 Sep. 2018 Neutron stars contain a small fraction of protons and electrons. Chris Lee, Ars Technica, "High-energy protons emitted after hooking up with neutrons," 16 Aug. 2018 When the clams are pressing their feet against a surface, even a fairly small number of protons will be concentrated together, leading to a substantial drop in pH at that spot. Veronique Greenwood, New York Times, "This Burrowing Clam Is Not Boring. It Uses Acid to Make Its Home.," 14 June 2018 In other words, the ratio of baryons, which include protons and neutrons, to photons, which light is made of, would have to shrink. Charles Q. Choi, Space.com, "Why Alternate Universes Might Also Host Life Around their Stars," 26 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'proton.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of proton

1920, in the meaning defined above

History and Etymology for proton

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

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Statistics for proton

Last Updated

4 Feb 2019

Look-up Popularity

Time Traveler for proton

The first known use of proton was in 1920

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More Definitions for proton

proton

noun

English Language Learners Definition of proton

physics : a very small particle of matter that is part of the nucleus of an atom and that has a positive electrical charge

proton

noun
pro·​ton | \ ˈprō-ˌtän \

Kids Definition of proton

: a very small particle that exists in the nucleus of every atom and has a positive charge of electricity

proton

noun
pro·​ton | \ ˈprō-ˌtän \

Medical Definition of proton

: 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

Other Words from proton

protonic \ prō-​ˈtän-​ik \ adjective

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More from Merriam-Webster on proton

Rhyming Dictionary: Words that rhyme with proton

Spanish Central: Translation of proton

Nglish: Translation of proton for Spanish Speakers

Britannica.com: Encyclopedia article about proton

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