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

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

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Hypothesized by Ettore Majorana in 1937, this particle is its own antiparticle. Neil Savage, Scientific American, "What Are the Limits of Manipulating Nature?," 8 May 2018 For technical reasons, LSND researchers actually studied μ antineutrinos—the antiparticles of μ neutrinos—traveling just 30 meters to their detector. Adrian Cho, Science | AAAS, "Reports of sterile neutrino’s resurrection may be greatly exaggerated," 4 June 2018 An electron and its antiparticle, a positron, have identical properties except for charge, but the charge of the Majorana particle would be zero. Neil Savage, Scientific American, "What Are the Limits of Manipulating Nature?," 8 May 2018 Peper only tantalizes us with the vaguest contours of what the feed and its antiparticle, Analog, are like. Cyrus Farivar, Ars Technica, "Bandwidth is the techno-thriller novel that we need right now," 6 May 2018 The theory possesses a kind of mathematical symmetry that requires particles and antiparticles to be mirror opposites. Adrian Cho, Science | AAAS, "Atoms and antiatoms haven’t crashed Albert Einstein’s theory of relativity—yet," 4 Apr. 2018 Thanks to quantum uncertainty, the vacuum roils with particle-antiparticle pairs flitting in and out of existence too fast to detect directly. Adrian Cho, Science | AAAS, "Hawking’s final quest: saving quantum theory from black holes," 20 Mar. 2018 The intensity is large enough that electrons and their antiparticle, positrons, are produced from the vacuum. Chris Lee, Ars Technica, "Excessively large laser is key to creating gamma ray sources," 9 Nov. 2017 By smashing together electrons and their antiparticle, positrons, the experiments produced large numbers of Y(4260), which lives for only 10-23 seconds before falling apart into other particles. Adam Mann, WIRED, "Mysterious Subatomic Particle May Represent Exotic New Form of Matter," 17 June 2013

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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