The hypothetical supersymmetric counterpart of the photon, with spin −1/2.
- ‘The photon, a boson, has a fermion partner called the photino.’
- ‘Also, the next vibration of the string includes a photino or particle which may make up most of the dark matter in the Universe.’
- ‘Another popular notion is supersymmetry, which predicts that all particles have shadowy ‘superpartners,’ with names such as selectrons, smuons and photinos.’
1970s: from photon + -ino from neutrino.