electron

American  

[ih-lek-tron] / ɪˈlɛk trɒn /

noun

1. Also called negatron.  Physics, Chemistry. an elementary particle that is a fundamental constituent of matter, having a negative charge of 1.602 × 10 −19 coulombs, a mass of 9.108 × 10 −31 kilograms, and spin of ½, and existing independently or as the component outside the nucleus of an atom.

2. Electricity. a unit of charge equal to the charge on one electron.

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electron British  

/ ɪˈlɛktrɒn /

noun

1. a stable elementary particle present in all atoms, orbiting the nucleus in numbers equal to the atomic number of the element in the neutral atom; a lepton with a negative charge of 1.602 176 462 × 10 ^–19 coulomb, a rest mass of 9.109 381 88 × 10 ^–31 kilogram, a radius of 2.817 940 285 × 10 ^–15 metre, and a spin of 1/ 2

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electron Scientific  

/ ĭ-lĕk′trŏn′ /

1. A stable elementary particle in the lepton family having a mass at rest of 9.107 × 10 ^{- 28} grams and a negative electric charge of approximately 1.602 × 10 ^{- 19} coulombs. Electrons orbit about the positively charged nuclei of atoms in distinct orbitals of different energy levels, called shells. Electrons are the primary charge carriers in electric current.

2. Compare positron See also electromagnetism elementary particle ion See Table at subatomic particle

3. A positron or a negatron.

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electron Cultural  

1. An elementary particle with a negative charge and a very small mass. Electrons are normally found in orbits around the nucleus of an atom. The chemical reactions that an atom undergoes depend primarily on the electrons in the outermost orbits (the valence electrons).

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Discover More

The movement of large numbers of electrons through conductors constitutes an electric current.

Etymology

Origin of electron

Term first suggested in 1891 by Irish physicist G. J. Stoney (1826–1911); electr(ic) + -on (from the names of charged particles, as ion, cation, anion ) with perhaps accidental allusion to Greek ḗlektron amber ( electric )

Compare meaning

How does electron compare to similar and commonly confused words? Explore the most common comparisons:

• proton vs. electron

Example Sentences

During later tests, the areas previously exposed to the electron beam behaved differently and displayed distinct colors.

From Science Daily • Mar. 31, 2026

However, when viewed with an electron microscope, the QR code can be clearly and reliably read.

From Science Daily • Mar. 29, 2026

That atom then stabilizes itself by pulling an electron from a nearby atom, while the released energy ionizes a third neighbor.

From Science Daily • Mar. 24, 2026

Even though they are only a single layer of atoms, they can host tightly bound excitons, which are electron and hole pairs that interact strongly with light.

From Science Daily • Mar. 24, 2026

By put it in the beam, he meant “look at it using the electron microscope,” which is much more powerful than a light microscope, and can see deeper into the universe within.

From "The Hot Zone" by Richard Preston

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