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

The casing worked for the electrons but couldn’t keep protons at bay, which degraded the photon detectors. — Ameya Paleja, Interesting Engineering, 28 Sep. 2026

At this time, the light from the first stars was stripping electrons from the hydrogen gas between them, a process called ionization. — Robert Lea, Space.com, 25 Sep. 2026

Other than its peculiar curvature, the interior of the anti-de Sitter snow globe is a lot like our universe, filled with electrons and atoms. — Quanta Magazine, 25 Sep. 2026

Atomic optical clocks keep time by using electrons as a pendulum. — New Atlas, 24 Sep. 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