noun · 2 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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UK:/ˈn(j)uː.tɹɒn/
US:/ˈnu.tɹɑn/
US:Recorded audio is listed in the source snapshot.
Southern-England:Recorded audio is listed in the source snapshot.
CMU ARPABET:N UW1 T R AA2 N
Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.
1
noun
Meaning 1
A subatomic particle forming part of the nucleus of an atom and having no charge; it is a combination of an up quark and two down quarks.
Definition source: English Wiktionary via Wiktextract
an elementary particle with 0 charge and mass about equal to a proton; enters into the structure of the atomic nucleus
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
Broader terms: nucleon
History
Etymology
From neutral + -on; by surface analysis, neutr(o)- + -on. Coined by Scottish-Australian physicist William Sutherland in 1899 in a paper in the Philosophical Magazine. Subsequent usage was sporadic and theoretical, sometimes referring to neutrinos rather than neutrons, and the modern sense was reintroduced alongside proton by Ernest Rutherford in 1920.
Across languages
Translations
65 source translations are retained for this English entry.
