positron

noun

pos·​i·​tron ˈpä-zə-ˌträn 

: 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

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

Neutron stars also have some of the strongest magnetic fields known in the universe — up to 10 trillion times the power of a refrigerator magnet, and enough turn gamma rays into electrons and positrons in a way manmade particle accelerators cannot hope to do, NASA explained. —Adam Harrington, CBS News, 9 Feb. 2026

That was because gamma-ray photons, individual particles of light, were rapidly transformed into pairs of electrons and positrons. —Robert Lea, Space.com, 4 Feb. 2026

Word History

Etymology

positive + -tron (as in electron)

First Known Use

1933, in the meaning defined above

Phrases Containing positron

• positron-emission tomography

Rhymes for positron

• aileron
• antiphon
• autobahn
• carillon
• castellan
• celadon
• cephalon
• chitosan
• cynodon
• denouement
• deuteron
• echelon

Kids Definition

positron

noun

pos·​i·​tron ˈpäz-ə-ˌträn 

: 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 

: 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