[an-tee-noo-tron, -nyoo-, an-tahy-]
noun Physics.
  1. an elementary particle having no charge and having a mass and spin equal to that of the neutron but with magnetic moment opposite to that of the neutron; the antiparticle of the neutron.
  1. Also an·ti-neu·tron. opposing the building, stockpiling, or use of neutron bombs: The antineutron lobby was outnumbered.

Origin of antineutron

First recorded in 1940–45; anti- + neutron Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for antineutron


  1. the antiparticle of a neutron; a particle having the same mass as the neutron but a magnetic moment of opposite sign
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

antineutron in Science


[ăn′tē-nōōtrŏn′, ăn′tī-]
  1. The antiparticle that corresponds to the neutron.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.