electron

American  

[ih-lek-tron] / ɪˈlɛk trɒn /

noun

• electrons
  plural

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.

Other Word Forms

Noun Inflected Forms

• electrons
  plural

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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 )

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Compare meaning

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

• proton vs. electron

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Explanation

If you take chemistry, you will learn about electrons. Electrons are the smallest of the particles that make up an atom, and they carry a negative charge. The number of protons and electrons is equal in a neutral atom. The hydrogen atom, for example, has just one electron and one proton. The uranium atom, on the other hand, has 92 protons, and therefore, 92 electrons. An electron is so small that it cannot be seen with the naked eye, but neither can the atom itself.

Example Sentences

See Examples For:

electron electrons

Reaching that goal may require another improvement: using a tightly focused electron beam rather than the defocused beam currently needed to produce sufficient contrast without the laser phase plate.

From Science Daily ● Oct. 22, 2026

Rather than simply illuminating a specimen, the laser interacts directly with the microscope's electron beam, altering its phase to increase image contrast.

From Science Daily ● Oct. 22, 2026

One of the biggest problems is that an electron beam can heat and eventually damage the specimen being examined.

From Science Daily ● Oct. 22, 2026

By combining advanced mathematical approaches to symmetry with spintronics, which studies how electron spin can be used in electronic devices, the researchers identified a previously unrecognized pattern of magnetic behavior.

From Science Daily ● Oct. 18, 2026

When a bullet hits an electron, it gives it a nudge.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

They are also important to spintronics, which explores ways to use the magnetic properties of electrons in electronic devices, and to research involving topological quantum effects.

From Science Daily ● Oct. 26, 2026

Silicon spin qubits store this information using the spin of individual electrons confined within silicon.

From Science Daily ● Oct. 26, 2026

"You need to account for complex interactions between the electrons and surrounding atoms, and that's challenging in realistic solids represented by models with hundreds or thousands of atoms"

From Science Daily ● Oct. 23, 2026

One important example involves fermions, a category of particles that includes electrons.

From Science Daily ● Oct. 18, 2026

Even so, the number of useful ways of putting nucleic acids together is stupefyingly large—probably far greater than the total number of electrons and protons in the universe.

From "Cosmos" by Carl Sagan

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