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 Someone to do jobs that are probably fatal, like clean out the antimatter chamber, or explore a totally unknown environment. Tom Shippey, WSJ, 13 May 2022 Antiprotons are the antimatter version of protons, with exactly the same mass but opposite charge. John Conway, The Conversation, 14 Apr. 2022 Doing these measurements presented a significant challenge, however, and not just because of the tendency of matter and antimatter to annihilate each other. John Timmer, Ars Technica, 16 Mar. 2022 Both of these types of antimatter likely form during the collision of cosmic rays. Jennifer Leman, Popular Mechanics, 7 Oct. 2021 And the decay of heavy neutrinos moments after the Big Bang has been suggested as the possible reason why there’s so much more matter than antimatter in the universe. Quanta Magazine, 28 Oct. 2021 That question is exactly what drives so much research into antimatter. Caroline Delbert, Popular Mechanics, 21 Sep. 2021 The Blakes’ house and Faden’s workshop are matter and antimatter, absolute contraries. Alan Jacobs, Harper's Magazine, 12 Oct. 2021 So how did the researchers at Helmholtz-Zentrum Dresden-Rossendorf figure out how to generate antimatter? Caroline Delbert, Popular Mechanics, 21 Sep. 2021 See More

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.

First Known Use of antimatter

1934, in the meaning defined above

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Time Traveler for antimatter

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The first known use of antimatter was in 1934

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Last Updated

27 May 2022

Cite this Entry

“Antimatter.” Dictionary, Merriam-Webster, Accessed 26 Jun. 2022.

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