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

That sets a maximum sustainable energy scale for the proton to be 5 × 1019 electron-volts. —Big Think, 30 Jan. 2026

The freed electrons drift toward readout planes at either end, creating a detailed 3D image of each particle’s trajectory. —Tejasri Gururaj, Interesting Engineering, 29 Jan. 2026

That's like the electrons finding their best spot inside a molecule that lowers the energy. —John Werner, Forbes.com, 28 Jan. 2026

Using excess heat for community power effectively allows electrons to be used twice, argued Matthew Powell, who conducts research at EnergiRaven. —April Roach,tasmin Lockwood, CNBC, 27 Jan. 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