an·​ti·​mat·​ter | \ ˈan-tē-ˌma-tər, ˈan-ˌtī- How to pronounce antimatter (audio) \

Definition of antimatter

: matter composed of antiparticles

Examples of antimatter in a Sentence

Recent Examples on the Web The $2 billion spectrometer — launched to the space station in 2011 — could resume its hunt for elusive antimatter and dark matter in the coming days., "News of the Day From Across the Nation," 25 Jan. 2020 No one has ever measured an antimatter particle falling, so the hope is its behavior can reveal something new about gravity. Sophia Chen, Wired, "How the Extreme Art of Dropping Stuff Could Upend Physics," 2 Jan. 2020 Figuring out how neutrinos acquire mass may resolve other, seemingly related mysteries, such as why there is more matter than antimatter in the universe. Quanta Magazine, "How the Neutrino’s Tiny Mass Could Help Solve Big Mysteries," 15 Oct. 2019 Launched to the space station in 2011, the AMS was built to study high-energy cosmic rays to glean clues about what happened to the antimatter presumably created during the big bang in equal measure with normal matter. William Harwood, CBS News, "Spacewalkers replace coolant pumps on $2 billion cosmic ray detector," 2 Dec. 2019 This everyday phenomenon is powerful enough to produce antimatter and transform atoms, leaving a radioactive cloud in its wake. John Timmer, Ars Technica, "Data from the International Space Station confirms: Lightning is insane," 10 Dec. 2019 The $2 billion spectrometer has been up there hunting for antimatter and dark matter for 8 ½ years, longer than anticipated. Washington Post, "Spacewalking astronauts add new pumps to cosmic detector," 2 Dec. 2019 The $2 billion spectrometer is searching for elusive antimatter and dark matter., "Italian astronaut Luca Parmitano and U.S. astronaut Andrew Morgan ventured out Friday with dozens of tools and four new pumps for the Alpha Magnetic Spectrometer. NASA considers these spacewalks the most difficult since the Hubble Space Telescope repairs a few decades ago.," 15 Nov. 2019 Intriguingly, theory suggests that differences in the behavior of neutrinos and antineutrinos could be what allows matter to dominate over antimatter in the universe. Quanta Magazine, "Neutrinos Lead to Unexpected Discovery in Basic Math," 13 Nov. 2019

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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The first known use of antimatter was in 1950

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Last Updated

4 Feb 2020

Cite this Entry

“Antimatter.” Dictionary, Merriam-Webster, Accessed 20 Feb. 2020.

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