What does antineutrino mean?
An antineutrino is the antiparticle of the neutrino, one of the most abundant yet elusive particles in the universe. Like the neutrino, it carries no electric charge and has an extremely small mass, but it possesses the opposite lepton number, which distinguishes it from its matter counterpart. Antineutrinos are produced abundantly in beta-minus decay, in nuclear reactors, and in the radioactive decay processes occurring inside the Earth. Because they interact only via the weak nuclear force and gravity, they pass through ordinary matter almost entirely unimpeded — trillions stream through every person each second without effect. The term belongs firmly to the vocabulary of particle physics, appearing in scientific literature and science journalism, often qualified by flavour labels such as 'electron antineutrino'. Its study has proved scientifically valuable, enabling experiments on neutrino oscillation, reactor monitoring, and imaging of the Earth's internal heat through so-called geoneutrinos.
nounThe antiparticle of the neutrino, a subatomic particle with no electric charge and very little mass that is produced in beta decay and other nuclear reactions.
- The antiparticle of the neutrino, having no electric charge, very small mass, and opposite lepton number to the neutrino.
"Nuclear reactors emit vast numbers of electron antineutrinos, which physicists detect to study the properties of these elusive particles."
"The Kamioka Liquid-scintillator Antineutrino Detector was built to observe geoneutrinos streaming up from deep within the Earth."
"In beta-minus decay, a neutron transforms into a proton while emitting an electron and an antineutrino."
Regular English plural; used freely in scientific contexts when referring to populations of these particles.
"Reactor antineutrinos have been used to test whether these particles change flavour as they travel."
Trillions of antineutrinos from the Sun and Earth's radioactive interior pass through your body every second without leaving any trace.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of antineutrino
The word 'antineutrino' was coined in the mid-twentieth century following Wolfgang Pauli's 1930 hypothesis of the neutrino and its subsequent experimental confirmation in the 1950s. It combines the prefix 'anti-', from Greek 'anti' meaning 'against' or 'opposite', with 'neutrino', an Italian diminutive coined by physicist Enrico Fermi from Italian 'neutro', itself from Latin 'neuter' meaning 'neither'. Cognates sharing this Latin root include 'neutral' and 'neutron'. The term entered English scientific usage as physicists confirmed that the particle emitted alongside electrons in beta decay was distinct from the neutrino itself.
How antineutrino is actually used
Strictly a technical term of particle physics, used almost exclusively in scientific writing and journalism about physics. Plural is standard English 'antineutrinos'. Often used with a flavour label such as 'electron antineutrino' or 'muon antineutrino'.
Easily confused with antineutrino
A neutrino and an antineutrino are antiparticles of each other; the antineutrino has opposite lepton number and is typically produced in beta-minus decay, whereas the neutrino arises in beta-plus decay and electron capture.