: 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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Then, a few months later, an even heavier antiparticle — anti-hyperhelium-4 that is made from two anti-protons, an anti-neutron and an anti-hyperon — was detected by the ALICE (A Large Ion Collider Experiment) instrument at the LHC.
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Keith Cooper, Space.com, 25 Dec. 2024
There’s a very real possibility that neutrinos are also their own antiparticles.
—Paul Sutter, Ars Technica, 11 June 2024
But through some very complex and exceedingly technical processes, a particle that is its own antiparticle can acquire a mass.
—Paul Sutter, Ars Technica, 11 June 2024
If dark matter particles are also their own antiparticles, as many dark matter theories posit, then within these collapsing clouds, those particles would have collided with one another and self-annihilated.
—Stephanie Pappas, Scientific American, 20 July 2023
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Keith Cooper, Space.com, 25 Dec. 2024
There’s a very real possibility that neutrinos are also their own antiparticles.
—Paul Sutter, Ars Technica, 11 June 2024
But through some very complex and exceedingly technical processes, a particle that is its own antiparticle can acquire a mass.
—Paul Sutter, Ars Technica, 11 June 2024
If dark matter particles are also their own antiparticles, as many dark matter theories posit, then within these collapsing clouds, those particles would have collided with one another and self-annihilated.
—Stephanie Pappas, Scientific American, 20 July 2023
See all Example Sentences for antiparticle
Dictionary Entries Near antiparticle
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“Antiparticle.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/antiparticle. Accessed 22 Jan. 2025.
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antiparticle
noun
an·ti·par·ti·cle
ˈant-i-ˌpärt-i-kəl 
ˈan-ˌtī-
: an elementary particle identical to another elementary particle in mass but opposite to it in electric or magnetic properties
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