# electron

/ˌɪˈɫɛktɹɑn/ (US) · /ɪlˈɛktɹɒn/ (UK)

Source: https://englishreference.com/word/electron
Updated: 2026-06-20

## Senses

### 1. subatomic particle

noun · CEFR B2 · Technical

a very small part of an atom that carries a negative electrical charge.

For teachers: a subatomic particle with a negative elementary electric charge that orbits the atomic nucleus.

- Electricity is created when electrons move from one atom to another through a wire.
- In a covalent bond, atoms achieve stability by sharing pairs of electrons, effectively filling their outermost shells.

Usage: Countable noun; often used in the plural when discussing electrical flow or chemical bonding.

### 2. magnesium alloy

noun · CEFR C2 · Archaic · Technical

a type of strong, light metal made from magnesium that was used in the past.

For teachers: a trademarked series of magnesium alloys containing varying amounts of aluminium or zinc, historically significant in early twentieth-century engineering.

- The old airplane engine was made from a lightweight electron alloy.
- The structural integrity of the vintage airframe relied on electron components, which offered an exceptional strength-to-weight ratio for the period.

Teaching tip: This sense is largely historical and refers to a specific brand of alloy; modern speakers almost exclusively use the word to refer to the subatomic particle.

## Examples

- An electron moves around the center of an atom.
- In a metal wire, electricity flows when electrons move from one atom to another in a steady stream.
- The chemical properties of an element are largely determined by the arrangement of electrons in its outermost shell, which dictates how the atom bonds with others.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.