positron

noun

pos·​i·​tron ˈpä-zə-ˌträn How to pronounce positron (audio)
: a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron

called also antielectron

Examples of positron in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The cloud’s electric field would push the positron backward close to where the avalanche began. Quanta Magazine, 6 May 2026 For instance, light particles like positrons (or electrons, in this experiment) need extremely fast oscillations, gigahertz (GHz) frequencies, to stay confined. Rupendra Brahambhatt, Interesting Engineering, 11 Apr. 2026 The experiment was to measure the angle at which events that produced an electron-positron pair had those two particles, the electron and the positron, made relative to one another. Big Think, 19 Mar. 2026 Researchers used positron emission tomography, or PET, brain imaging on 32 people with AUD and 29 controls. Christopher Gardner, Hartford Courant, 16 Mar. 2026 See All Example Sentences for positron

Word History

Etymology

positive + -tron (as in electron)

First Known Use

1933, in the meaning defined above

Time Traveler
The first known use of positron was in 1933

Cite this Entry

“Positron.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/positron. Accessed 12 May. 2026.

Kids Definition

positron

noun
pos·​i·​tron ˈpäz-ə-ˌträn How to pronounce positron (audio)
: a positively charged particle having the same mass and size of charge as the electron

Medical Definition

positron

noun
pos·​i·​tron ˈpäz-ə-ˌträn How to pronounce positron (audio)
: a positively charged particle having the same mass and magnitude of charge as the electron and constituting the antiparticle of the electron

called also positive electron

More from Merriam-Webster on positron

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster