ion UK /ˈaɪən/US /ˈaɪ.ɑn/noun 1/ˈaɪˌoʊn/ phrase 1forms 1 noun1 •An atom or group of atoms bearing an electrical charge, such as the sodium and chlorine atoms in a salt solution. ion /ˈaɪˌoʊn/ phrase1 •(slang) I don't.ion know what 2 do formsions
