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

In comparing isotopes of an element like uranium, the atomic number stays the same, but the isotope number — the sum of the protons and neutrons in a nucleus — can differ. Umair Irfan, Vox, "Uranium enrichment will be a key point in talks with North Korea. Here’s what it is.," 11 June 2018 Nikola's hydrogen system creates electricity by splitting hydrogen electrons from the protons. Russ Mitchell, latimes.com, "Nikola, a Tesla competitor, scores big electric truck order from Anheuser-Busch," 3 May 2018 An axion is a hypothetical particle that was invented 41 years ago to solve a problem in the theory of the strong nuclear force, which binds particles called quarks to make protons and neutrons. Adrian Cho, Science | AAAS, "Search for superlight dark matter particles heats up," 9 Apr. 2018 But literally quadrillions of proton collisions in the collider later, nothing new has emerged. Jason Daley, Smithsonian, "Researchers Find More Evidence for the Higgs Boson," 10 July 2018 For example, why is the mass of a proton 1836.15 times greater than that of the electron? Dan Falk /, NBC News, "What is the multiverse?," 22 May 2018 These are extremely energetic protons and atomic nuclei moving through space at almost the speed of light. Author: Sarah Kaplan, Anchorage Daily News, "In a cosmic first, scientists detect ‘ghost particles’ from a distant galaxy," 12 July 2018 These are extremely energetic protons and atomic nuclei moving through space at almost the speed of light. Sarah Kaplan, chicagotribune.com, "In a cosmic first, scientists detect 'ghost particles' from a distant galaxy," 12 July 2018 If a hydrogen atom were the size of Earth, the proton at its center would fit inside the Ohio State football stadium. Author: Sarah Kaplan, Anchorage Daily News, "In a cosmic first, scientists detect ‘ghost particles’ from a distant galaxy," 12 July 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

16 Sep 2018

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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Comments on proton

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