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

Unlike the breeze that blows here on Earth, this wind is made up of electrons and protons from the sun's corona. —Meredith Garofalo, Space.com, 16 Feb. 2025

Miniaturized accelerators could advance radiation therapy for cancer treatment, providing high-energy electron or ion beams with unprecedented precision. —The Physics Arxiv Blog, Discover Magazine, 14 Feb. 2025

Image The laser method makes use of how some minerals glow when electrons absorb and then re-emit light. —Elizabeth Landau, New York Times, 14 Feb. 2025

Pain and play often share space in Shakespeare’s story, like so many protons and electrons sparking off each other. —Sara Holdren, Vulture, 12 Feb. 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

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