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 With an extra proton, the atom will now be copper-63, the next element in the periodic table. Rhett Allain, WIRED, 23 Feb. 2024 Aside from high day-to-day expenses, the proton beam center is getting hit by extremely high interest rates on the company’s debt and depreciation of the equipment. Bob Herman Reprints, STAT, 5 Feb. 2024 Together, Ghostbusters old and new will join forces, putting on their proton packs — Melnitz included — to save New York. Abbey White, The Hollywood Reporter, 29 Jan. 2024 The treatment usually consists of maximal safe resection followed by total brain and spine radiation, often with proton therapy if available, with extra radiation to the tumor site. Dominique Fluker, Essence, 12 Jan. 2024 Researchers are also exploring treatments using ions heavier than protons to more effectively damage DNA in cancer cells and enhance the efficacy of radiation therapy. Behzad Ebrahimi, Discover Magazine, 5 Jan. 2024 Scientists could use these pulses, which are even faster than attosecond pulses, to study the motion of particles like protons within the nucleus. Niranjan Shivaram, The Conversation, 4 Oct. 2023 Some new physics models tweak dark energy, adding a surge of cosmic acceleration in the early moments of the universe, before electrons and protons glommed onto each other. Quanta Magazine, 19 Jan. 2024 When the universe began to cool down, the protons and neutrons began to combine into ionized atoms of hydrogen. Laura Baisas, Popular Science, 18 Jan. 2024

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.

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 18 Mar. 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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