- An atom or molecule with a net electric charge due to the loss or gain of one or more electrons: [with modifier]: hydrogen ions a sulphate ion See also cation, anion.More example sentences
- Some compounds have polyatomic ions, where the ion is composed of two or more atoms.
- The charge on the complex ion is the sum of the charges on the metal ion and the ligands.
- At that stage, the electrons and ions combined into neutral atoms that no longer scattered the radiation.
mid 19th century: from Greek, neuter present participle of ienai 'go'.
More definitions of ionDefinition of ion in:
- The US English dictionary