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


photon + -ino (as in neutrino)

First Known Use

1977, in the meaning defined above

Time Traveler
The first known use of photino was in 1977

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Dictionary Entries Near photino

Cite this Entry

“Photino.” Dictionary, Merriam-Webster, Accessed 29 May. 2024.

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