neutron

noun

neu·​tron ˈnü-ˌträn How to pronounce neutron (audio)
ˈnyü-
: an uncharged elementary particle that has a mass nearly equal to that of the proton and is present in all known atomic nuclei except the hydrogen nucleus
neutronic adjective

Examples of neutron 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.
Ruotsalainen observed that the atomic nuclei, which consist of electrically positive protons and electrically neutral neutrons, moved in circular paths inside the trap, under a powerful magnetic field. Georgina Jedikovska, Interesting Engineering, 8 Oct. 2025 This new particle, the neutron, finally completed the basic picture of the atom. Ethan Siegel, Big Think, 30 Sep. 2025 Because protons and neutrons are shielded from many environmental disturbances, those transitions may carry the subtle imprint of dark matter. New Atlas, 16 Sep. 2025 Understanding quark-gluon plasma could reveal what conditions in the universe were like in its first microseconds and how this gave way to protons and neutrons — and eventually, the matter that populates the cosmos today. Robert Lea, Space.com, 5 Sep. 2025 See All Example Sentences for neutron

Word History

Etymology

probably from neutral

First Known Use

1921, in the meaning defined above

Time Traveler
The first known use of neutron was in 1921

Cite this Entry

“Neutron.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/neutron. Accessed 19 Oct. 2025.

Kids Definition

neutron

noun
neu·​tron ˈn(y)ü-ˌträn How to pronounce neutron (audio)
: an uncharged atomic particle that has a mass nearly equal to that of the proton and is present in all known atomic nuclei except the hydrogen nucleus

Medical Definition

neutron

noun
neu·​tron ˈn(y)ü-ˌträn How to pronounce neutron (audio)
: an uncharged elementary particle that has a mass nearly equal to that of the proton and is present in all known atomic nuclei except the hydrogen nucleus

More from Merriam-Webster on neutron

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