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 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 The inflaton field would have roiled with quantum ripples of energy — spontaneously created pairs of particles and antiparticles. Quanta Magazine, "Joint Dust Analysis Deflates Big Bang Signal," 30 Jan. 2015 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

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.” The Dictionary, Merriam-Webster Inc., Accessed 23 January 2020.

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out of the ordinary or unreasonable

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