photino

noun

pho·​ti·​no

fōˈtē(ˌ)nō

plural -s

: 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

Word History

Etymology

photon + -ino (as in neutrino)

First Known Use

1977, in the meaning defined above

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