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English definition of “ion”

ion

noun [C] uk   /ˈaɪ.ɒn/ us    /-ɑːn/ specialized
an atom or small group of atoms that has an electrical charge because it has added or lost one or more electrons Atoms, molecules and sub-atomic particles
ionic
adjective uk   /aɪˈɒn.ɪk/ us    /-ˈɑː.nɪk/
ionic bondingAtoms, molecules and sub-atomic particles
(Definition of ion noun from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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