an·​ti·​mat·​ter | \ˈan-tē-ˌma-tər, ˈan-ˌtī-\

Definition of antimatter 

: matter composed of antiparticles

Examples of antimatter in a Sentence

Recent Examples on the Web

In very large stars, pressures at the core are thought eventually to produce antimatter, causing an explosion so violent that the star simply disintegrates without leaving any remnants at all. Davide Castelvecchi, Scientific American, "Here Come the Waves," 23 Apr. 2018 The antimatter should have annihilated all the regular matter, leaving nothing left over. Avery Thompson, Popular Mechanics, "New Experiment Hints at Why the Universe Is Made of Something Rather Than Nothing," 8 Aug. 2016 Gott suggests that highly efficient antimatter fuel could be the key and other world agencies and scientists also think such a fuel could be a potentially invaluable piece to interstellar travel. Matt Blitz, Popular Mechanics, "We Already Know How To Build a Time Machine," 28 May 2018 This picture at first seemed just a manner of speaking but soon led to the discovery of antimatter. Philip Ball, Scientific American, "Quantum Physics May Be Even Spookier Than You Think," 21 May 2018 In addition, these weird particles may hold the key to some of the biggest mysteries about the universe, including why matter won out over antimatter early after the Big Bang, said. Doyle Rice, USA TODAY, "'Ghost particles' from outer space: Scientists discover distant source of neutrinos," 12 July 2018 If that happens, the antimatter annihilates, producing a burst of energy. Sophie Weiner, Popular Mechanics, "How To Make and Trap Antimatter," 1 Apr. 2017 One key test of matter-antimatter symmetry is to compare the frequencies of light absorbed by hydrogen and antihydrogen atoms. Adrian Cho, Science | AAAS, "Atoms and antiatoms haven’t crashed Albert Einstein’s theory of relativity—yet," 4 Apr. 2018 In a project that began last month, researchers will transport antimatter by truck and then use it to study the strange behaviour of rare radioactive nuclei. Elizabeth Gibney, Scientific American, "Physicists Plan Antimatter's First Outing--in a Van," 21 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'antimatter.' 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 antimatter

1950, in the meaning defined above

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25 Nov 2018

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The first known use of antimatter was in 1950

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living or existing for a long time

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