Definition of electron in US English:



  • A stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.

    The electron's mass is about 9 × 10²⁸g, 1,836 times less than that of the proton. Electrons orbit the positively charged nuclei of atoms and are responsible for binding atoms together in molecules and for the electrical, thermal, optical, and magnetic properties of solids. Electric currents in metals and in semiconductors consist of a flow of electrons, and light, radio waves, X-rays, and much heat radiation are all produced by accelerating and decelerating electrons

    • ‘Electric current is the movement of electrons from one atom to another in a conductor.’
    • ‘For example, two electrons in an atom may differ in orbital angular momentum or in spin direction.’
    • ‘If this attraction is strong enough, it will pull the electrons free from the atoms.’
    • ‘It was soon discovered that the proton, the neutron, and the electron are not alone.’
    • ‘If the star were squeezed even more by gravity, the electrons could be forced to combine with protons to make more neutrons.’
    • ‘It was the antiparticle to the electron, later called the positron.’
    • ‘Most beta decays involve the emission of electrons from the nucleus as a neutron decays into an electron and a proton.’
    • ‘The antiparticle of the electron is the positron; there are also antiquarks and antineutrinos.’
    • ‘Nucleons like to pair up and form a shell structure, just as electrons do in atoms.’
    • ‘The electron and muon neutrinos are easier to produce and detect than the tau neutrino.’
    • ‘At that stage, the electrons and ions combined into neutral atoms that no longer scattered the radiation.’
    • ‘At the time, it was believed that electrons colliding with atoms always lost energy.’
    • ‘The outer shell of an oxygen atom holds six outer electrons, though it has room for eight.’
    • ‘It was like looking at the evenly spaced energy levels of electrons in an atom.’
    • ‘This species substitutes for a proton on an electron rich carbon in the benzene ring.’
    • ‘This means that an atom with eight electrons in its outermost energy level is very stable.’
    • ‘The ionization energy is the energy needed to remove an electron from a gaseous atom.’
    • ‘Like the Solar Wind, the magnetosphere is full of plasma, consisting of ions and electrons.’
    • ‘Chemical reactions inside the cell strip electrons from the hydrogen atoms to produce a voltage that can power a circuit.’
    • ‘It exists when the electrons of the atom are occupying the orbitals of lowest energy.’


Late 19th century: from electric + -on.