isospin

[ ahy-suh-spin ]

noun

, Physics.

1. isotopic spin.

isospin

/ ˈaɪsəʊˌspɪn /

noun

1. an internal quantum number used in the classification of elementary particles. Particles which have very similar properties except for those associated with their charge are regarded as forms of the same fundamental particle with different components of the isospin in a certain direction in an imaginary space Also calledisobaric spinisotopic spin

isospin

/ ī′sə-spĭn′ /

1. A vector quantity of quantum systems (especially subatomic particles) that is conserved in strong interactions and is used to characterize particles that are affected equally by the strong force but have other dissimilar properties, such as different electric charges. For example, protons and neutrons, which are indistinguishable with respect to strong force interactions, have the same isospin.
2. Also called isotopic spin
3. See also baryon number

Word History and Origins

Origin of isospin¹

By shortening