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

While the electron travels to the cathode to reduce carbon dioxide, the remaining hole simultaneously oxidizes the biomass molecule 5-Hydroxymethyl-2-furoic acid (HMFA), thereby executing two distinct chemical upgrades at the same time. —Mrigakshi Dixit, Interesting Engineering, 12 June 2026

Mostly depleted, the electrons then reach photosystem I, where another burst of sunshine kicks the flow back into high gear. —Quanta Magazine, 10 June 2026

The emission lines instead indicate the scattering of electrons, which is expected when a source of radiation is enshrouded by a vast and dense cocoon of gas. —Robert Lea, Space.com, 10 June 2026

Can’t play, won’t try Atoms are made of a central nucleus surrounded by electrons. —Chris Lee, ArsTechnica, 9 June 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