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antimatter

[an-tee-mat-er, an-tahy-]
noun Physics.
  1. matter composed only of antiparticles, especially antiprotons, antineutrons, and positrons.

Origin of antimatter

First recorded in 1950–55; anti- + matter
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for antimatter

Contemporary Examples of antimatter

Historical Examples of antimatter

  • On the average, one atom out of every ten million in the universe was an atom of antimatter.

    Psichopath

    Gordon Randall Garrett

  • The distribution was unequal of course; antimatter could not exist in contact with ordinary matter.

    Psichopath

    Gordon Randall Garrett

British Dictionary definitions for antimatter

antimatter

noun
  1. a form of matter composed of antiparticles, such as antihydrogen, consisting of antiprotons and positrons
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for antimatter
n.

also anti-matter, 1953, from anti- + matter (n.).

Online Etymology Dictionary, © 2010 Douglas Harper
antimatter in Science

antimatter

[ăn′tĭ-măt′ər]
  1. A form of matter that consists of antiparticles.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
antimatter in Culture

antimatter

In physics, matter made of antiparticles.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.