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

Where atomic clocks measure time by tracking electrons shifting between quantum states excited by a microwave oscillator, nuclear clocks turn inward, measuring transitions within the nucleus itself. —New Atlas, 16 Sep. 2025

The material enhances performance The team elucidated the material’s mechanism through a series of experimental analyses, including solid-state nuclear magnetic resonance (ssNMR) spectroscopy, electron spin resonance (EPR) spectroscopy, and theoretical calculations. —Mrigakshi Dixit, Interesting Engineering, 16 Sep. 2025

The color of the aurora depends on which gas is being excited by the electrons and on how much energy is being exchanged, NASA said. —Jenna Prestininzi, Freep.com, 16 Sep. 2025

Oxygenic photosynthesis takes electrons and hydrogen from water (H2O) and gives them to molecular carbon dioxide (CO2) to create glucose (C6H12O6). —Bruce Dorminey, Forbes.com, 15 Sep. 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