n. pl. neu·tri·nos Any of three electrically neutral leptons (the electron neutrino, muon neutrino, and tau neutrino—one in each of the three generations of elementary fermions) that have very small masses. [Italian, from neutrino, little neutral one : neutro, neuter, neutral (from Latin neuter, neutr-, neuter; see NEUTER) + -ino, diminutive suffix (from Latin -īnus, adjectival suffix; see –INE1). Coined by Enrico Fermi on the model of Italian neutrone, neutron, taken as the augmentative of Italian neutro.] |
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