Definitions for "Antiparticle"
Each particle has an anti-particle with the opposite electrical charge, color charge, and various other properties of the particle. Antiparticles and particles usually annihilate each other when they come close, releasing vast amounts of energy. Anti-matter and even some atoms of anti-hydrogen have been created in high energy particle accelerators. See also: particle, Debriefing, Journey - Anti-matter
The generic term for an anti-matter partner of a particle.
A particle of opposite charge but otherwise identical to its partner. Most of the observable universe consists of particles and matter, as opposed to antiparticles and antimatter.