(chemistry) Any radical that also carries an electric charge; typically, the charge and unpaired electron are associated with the same atom.

(chemistry) Any cation formed by the addition of a proton to the nitrogen or oxygen atom of an amide or derivative.

(chemistry) A cation formed by protonation of an amine - R₃NH⁺.

(organic chemistry) Any cation formed by the addition of a proton or other cationic species to an arene.

(obsolete, chemistry) An arenium ion.

(chemistry) the cation H₂As⁺ derived from arsine / (chemistry) any organic derivative of this cation

(organic chemistry) Any arenium ion derived from benzene or its derivatives.

(obsolete, organic chemistry) A benzenium ion.

(chemistry) any halonium ion in which the halogen is fluorine

(chemistry) any halonium ion in which the halogen is iodine