English word counterion comes from English counter- (In opposition to.), English ion
| Dictionary entry | Language | Definition |
|---|---|---|
| counter- | English (eng) | In opposition to. |
| ion | English (eng) | An atom or group of atoms bearing an electrical charge, such as the sodium and chlorine atoms in a salt solution. |
| counterion | English (eng) | (chemistry) Any ion of opposite charge to another in a solution or other electrochemical system. |