Oxford Dictionary English electron noun noun BrE BrE//ɪˈlektrɒn// ; NAmE NAmE//ɪˈlektrɑːn// (physics) Molecules and matter Add to my wordlistjump to other results a very small piece of matter (= a substance) with a negative electric charge, found in all atoms see also neutron, proton Wordfinderatomantiparticle, atom, electron, ion, neutron, nucleus, particle, positron, proton, valency Oxford Collocations DictionaryElectron is used before these nouns: beam, microscope, transfer, … See full entry See related entries: Molecules and matter Word Originlate 19th cent.: from electric + -on.See electron in the Oxford Learner's Dictionary of Academic EnglishSee electron in the Oxford Advanced American DictionaryCheck pronunciation: electron oxfordlearnersdictionaries.com