electron

noun

elec·​tron i-ˈlek-ˌträn 

: an elementary particle consisting of a charge of negative electricity equal to about 1.602 × 10⁻¹⁹ coulomb and having a mass when at rest of about 9.109 × 10⁻³¹ kilogram or about 1/1836 that of a proton

Examples of electron in a Sentence

Recent Examples on the Web

Antimatter — specifically the positron (anti-electron) — was proposed by Dirac in 1929 and discovered in 1932. —Big Think, 23 Feb. 2026

That matters because spin is a fundamental property of electrons and can be used to encode and transmit information. —Neetika Walter, Interesting Engineering, 20 Feb. 2026

The electron is magnetically oriented upward, say, in this imprint. —Quanta Magazine, 13 Feb. 2026

This energy often comes from the ionizing continuum, a powerful, high-energy flashlight from the black hole that strips electrons from atoms. —Paul Sutter, Space.com, 11 Feb. 2026

Word History

Etymology

electr- + -on entry 2

First Known Use

1891, in the meaning defined above

Phrases Containing electron

• Auger electron
• Auger electron spectroscopy
• electron cloud
• electron gas
• electron gun
• electron micrograph
• electron microscope
• electron multiplier
• electron optics
• electron probe
• electron transport
• electron tube
• electron volt
• free-electron laser
• scanning electron microscope
• valence electron

Rhymes for electron

• photoelectron

Kids Definition

electron

noun

elec·​tron i-ˈlek-ˌträn 

: an elementary particle that has a negative charge of electricity and travels around the nucleus of an atom

Medical Definition

electron

noun

elec·​tron i-ˈlek-ˌträn 

: an elementary particle consisting of a charge of negative electricity equal to about 1.602 × 10⁻¹⁹ coulomb and having a mass when at rest of about 9.109534 × 10⁻²⁸ gram or about ¹/₁₈₃₆ that of a proton