antiparticle

noun
an·​ti·​par·​ti·​cle | \ ˈan-tē-ˌpär-ti-kəl, ˈan-ˌtī- How to pronounce antiparticle (audio) \

Definition of antiparticle

: a subatomic particle identical to another subatomic particle in mass but opposite to it in electric and magnetic properties (such as sign of charge) that when brought together with its counterpart produces mutual annihilation especially : a subatomic particle not found in ordinary matter

Examples of antiparticle in a Sentence

Recent Examples on the Web Positronium is a volatile, short-lived atom that seems kind of like hydrogen but has a positron—an antiparticle considered opposite to an electron, sometimes even called an antielectron—instead of a proton. Caroline Delbert, Popular Mechanics, "Physicist Believes He Has What It Takes to Make a Gamma Ray Laser," 9 Dec. 2019 According to the dictates of Einsteinian relativity and the baffling laws of quantum theory, equal numbers of particles and their opposites, antiparticles, should have been created in the Big Bang that set the cosmos in motion. Dennis Overbye, New York Times, "Why the Big Bang Produced Something Rather Than Nothing," 15 Apr. 2020 Doing so allowed them to observe that in antihydrogen—which is composed of an antiproton and a positron, the electron’s antiparticle—jumps in energy levels known as the Lamb shift were identical to those seen in hydrogen. Jonathan O'callaghan, Scientific American, "Physicists Come Closer to Answering Question of Antimatter’s Scarcity," 19 Feb. 2020 But a particle and an antiparticle that materialize on either side of a black hole’s event horizon get dragged apart. Quanta Magazine, "Philosophers Debate New ‘Sonic Black Hole’ Discovery," 27 Aug. 2019 But a particle and an antiparticle that materialize on either side of a black hole’s event horizon get dragged apart. Wired, "A ‘Sonic Black Hole' Could Help Solve a Cosmic Paradox," 30 June 2019 But a particle and an antiparticle that materialize on either side of a black hole’s event horizon get dragged apart. Natalie Wolchover, WIRED, "A ‘Sonic Black Hole' Could Help Solve a Cosmic Paradox," 30 June 2019 The researchers were studying antineutrinos, a type of antiparticle. Avery Thompson, Popular Mechanics, "New Experiment Hints at Why the Universe Is Made of Something Rather Than Nothing," 8 Aug. 2016 The Italian scientists theorized the particles, which act as their own antiparticles, in 1937. David Grossman, Popular Mechanics, "Looks Like We Have a New State of Matter," 16 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'antiparticle.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of antiparticle

1934, in the meaning defined above

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The first known use of antiparticle was in 1934

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Cite this Entry

“Antiparticle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/antiparticle. Accessed 27 Jan. 2021.

More from Merriam-Webster on antiparticle

Britannica.com: Encyclopedia article about antiparticle

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