noun pho·ti·no \fōˈtē(ˌ)nō\

Definition of photino



  1. :  a hypothetical elementary particle that theories of supersymmetry require to be associated with the photon, to have mass, and to interact only very weakly with ordinary matter and that is postulated to be a constituent of the dark matter of the universe

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Origin and Etymology of photino

photon + -ino (as in neutrino)

First Known Use: 1977

Seen and Heard

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a rounded knoll or a ridge of ice

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