The definition of an electron is the lightest basic electrically-charged particle.(noun)
An example of an electron is what orbits the nucleus of an atom.
See electron in Webster's New World College Dictionary
Origin: coined (1891) by G. J. Stoney (1826-1911), Ir physicist < electr(ic) + -on
See electron in American Heritage Dictionary 4
noun Abbr. e
Origin: + -on1.
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