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An atom or a group of atoms that has acquired a net electric charge by gaining or losing one or more electrons.
[C19: from Greek, literally: going, from ienai to go]
i•on(ˈaɪ ən, ˈaɪ ɒn)
1. an atom or atom group electrically charged by the loss or gain of electrons, represented by a plus or a minus sign, as a cation (Na + , Ca + + ) or anion (Cl−).
2. one of the electrically charged particles formed in a gas by electric discharge.
[< Greek ión going, neuter present participle of iénai to go; term introduced by Michael Faraday in 1834]
a suffix, appearing in words of Latin origin, denoting action or condition, used to form nouns from stems of adjectives (communion; union) and verbs (legion; opinion; suspicion).Compare -tion.
[Middle English -ioun < Anglo-French < Latin -iōnem, acc. of -iō suffix forming nouns]
An atom or a group of atoms that has an electric charge. Positive ions, or cations, are formed by the loss of electrons; negative ions, or anions, are formed by the gain of electrons. See Note at charge.
1. An electrically charged atom or group of atoms.
2. An electrically charged atom or group of atoms.
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|Noun||1.||ion - a particle that is electrically charged (positive or negative); an atom or molecule or group that has lost or gained one or more electrons|
anion - a negatively charged ion
cation - a positively charged ion