The electron neutrino is a subatomic lepton elementary particle which has no net electric charge. Together with the electron it forms the first generation of leptons, hence its name electron neutrino. It was first hypothesized by Wolfgang Pauli in 1930, to account for missing momentum and missing energy in beta decay, and was discovered in 1956 by a team led by Clyde Cowan and Frederick Reines (see Cowan–Reines neutrino experiment).

A neutrino ( or ) (denoted by the Greek letter ν) is a lepton, an elementary particle with half-integer spin, that interacts only via the weak subatomic force  and gravity. The mass of the neutrino is tiny compared to other subatomic particles. They are the only identified candidate for dark matter, specifically hot dark matter.