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

These ultrashort flashes allow scientists to track how electrons reorganize around individual atomic sites, revealing how materials change their properties or how molecules transform during reactions. —Neetika Walter, Interesting Engineering, 17 Dec. 2025

All particles, like protons and the electrons, have antimatter siblings. —Dipangkar Dutta, The Conversation, 15 Dec. 2025

Francesco d'Errico and his colleagues used X-ray fluorescence and electron microscopy to analyze 16 lumps of ochre. —Jay Kakade december 10, New Atlas, 10 Dec. 2025

The Voyager 2 mission may have caught Uranus at a special time during which the ice giant's radiation belts were being supercharged with electrons accelerated by a similar process to what can drive geomagnetic storms on Earth. —Keith Cooper, Space.com, 10 Dec. 2025

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