pho·​ti·​no | \ fōˈtē(ˌ)nō \
plural -s

Definition of photino

: 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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First Known Use of photino

1977, in the meaning defined above

History and Etymology for photino

photon + -ino (as in neutrino)

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The first known use of photino was in 1977

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Cite this Entry

“Photino.” Dictionary, Merriam-Webster, Accessed 27 Sep. 2020.

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