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

This changes the alignment of the two ferromagnetic layers, which alters how easily electrons can tunnel through the insulating barrier (a quantum phenomenon known as tunnel magnetoresistance) and changes the sensor’s electrical resistance. — ArsTechnica, 5 Oct. 2026

Looking beyond the electron count The researchers focused on Tsai-type approximant crystals. — Rupendra Brahambhatt, Interesting Engineering, 4 Oct. 2026

In the early 1930s, scientists were just beginning to discover the extraordinary world hidden inside the atom, which is made up of a dense center, called the nucleus, with electrons orbiting around it. — Andrea Richard, The Conversation, 2 Oct. 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