# neutron

/ˈnuˌtɹɑn/ (US) · /njˈuːtɹɒn/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/neutron
Updated: 2026-05-06

## Definition

a tiny part of an atom that has no electrical charge. It sits in the center of the atom along with protons.

For teachers: a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.

## Examples

- A neutron has no electrical charge.
- Scientists study how the number of neutrons in an atom's nucleus determines its stability and isotopic identity.
- The discovery of the neutron allowed physicists to understand why atomic weights were higher than the total mass of the protons alone, leading to the development of modern nuclear models.

## Usage notes

- Commonly used in the plural when discussing atomic structure or nuclear reactions.

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