: 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
Examples of neutron in a Sentence
Recent Examples on the Web
The assembly is designed for use in fourth-generation fast neutron reactors and features mixed nitride uranium-plutonium (SNUPP) fuel that incorporates a liquid metal sublayer.
—
Aman Tripathi, Interesting Engineering, 18 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
Then, as the Universe cools further, nuclear fusion reactions can proceed, first forming deuterium out of protons and neutrons and then synthesizing heavier elements, like helium, and then (if there’s enough energy) lithium and heavier elements, after that.
—Ethan Siegel, Big Think, 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
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.
Aman Tripathi, Interesting Engineering, 18 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
Then, as the Universe cools further, nuclear fusion reactions can proceed, first forming deuterium out of protons and neutrons and then synthesizing heavier elements, like helium, and then (if there’s enough energy) lithium and heavier elements, after that.
—Ethan Siegel, Big Think, 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
Cite this Entry
“Neutron.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/neutron. Accessed 29 Sep. 2025.
Copy CitationKids Definition
neutron
noun
neu·tron
ˈn(y)ü-ˌträn 
: 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
: 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
Love words? Need even more definitions?
Merriam-Webster unabridged
Share