antiparticle

[ an-tee-pahr-ti-kuh l, an-tahy- ]

/ ˈæn tiˌpɑr tɪ kəl, ˈæn taɪ- /

noun Physics.

a particle all of whose properties, as mass, spin, or charge, have the same magnitude as but, where appropriate, the opposite sign of a specific elementary particle; neutral pions, photons, and gravitons are considered to be their own antiparticles: The positron is the antiparticle of the electron.Compare antimatter, annihilation(def 3).

Nearby words

Origin of antiparticle

First recorded in 1930–35; anti- + particle

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for antiparticle

antiparticle

/ (ˈæntɪˌpɑːtɪkəl) /

noun

any of a group of elementary particles that have the same mass and spin as their corresponding particle but have opposite values for all other nonzero quantum numbers. When a particle collides with its antiparticle, mutual annihilation occurs

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

Science definitions for antiparticle

antiparticle

[ ăn′tē-pär′tĭ-kəl, ăn′tī- ]

A subatomic particle, such as an antiproton, having the same mass as its corresponding particle, but opposite values of other properties such as charge, parity, spin, and direction of magnetic moment. For example, the antiparticle of the electron is the positron, which has a charge that is equal in magnitude to that of the electron but opposite in sign. Some particles, such as photons, are nondistinct from their antiparticles. When a particle and its antiparticle collide, they may annihilate one other and produce other particles.

Culture definitions for antiparticle

antiparticle

In physics, a rare form of subatomic matter that is a mirror image of normal matter. The antiparticle corresponding to an elementary particle has the same mass as the particle but is opposite in all other properties. The antiparticle corresponding to an electron is a positron, which has the same mass as an electron but a positive charge. Antiprotons have the same mass as protons but a negative charge. When matter and antimatter come together, the two particles annihilate each other, converting their mass into energy or into other types of particles.

Note

As far as scientists can tell, there is almost no naturally occurring antimatter in the universe, although it is possible to make antimatter in particle accelerators.