the GNU version of the Collaborative International Dictionary of English
n. The antiparticle of a neutron. It has the same mass as a neutron, but a spin and magnetic moment opposite that of the neutron.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. the antiparticle of a neutron
Word Usage
"When an antineutron collides with a beryllium nucleus, it annihilates one neutron, and the mutual annihilation releases around nine times the energy of a fissioning uranium atom."