nm. electron, negatively charged particle which is a fundamental component of matter and exists independently or outside the nucleus of an atom (Physics, Chemistry)

(n.) = electron.
Ex: For one, the record is made by a moving beam of electrons rather than a moving pointer, for the reason that an electron beam can sweep across the picture very rapidly indeed.
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* electrón de valencia = valence electron.
* rayo de electrones = electron beam.