Definition of isospin in English:

isospin

noun

Physics
  • A vector quantity or quantum number assigned to subatomic particles and atomic nuclei and having values such that similar particles differing only in charge-related properties (independent of the strong interaction between particles) can be treated as different states of a single particle.

    • ‘In short, they are similar to electric charge, isospin, and all the other internal quantum numbers of elementary particles.’
    • ‘This symmetry is related to the concept of isospin, and is not the same as charge conjugation.’

Origin

1960s: contraction of isotopic spin, isobaric spin.

Pronunciation:

isospin

/ˈīsəˌspin/