[an-tee-at-uh m, an-tahy-]
an atom of antimatter.
Origin of antiatom
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
an atom composed of antiparticles, in which the nucleus contains antiprotons with orbiting 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
An atom composed of antiparticles. An antiatom consists of positrons, antiprotons, and antineutrons. It has the same mass and spin as an ordinary atom, and the same amount of charge and magnetic moment, but the charge and magnetic moment are the opposite of those of an ordinary atom.
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