In chemistry, a superoxide is a compound that contains the superoxide ion, which has the chemical formula O2−. The systematic name of the anion is dioxide(1−). The reactive oxygen ion superoxide is particularly important as the product of the one-electron reduction of dioxygen O2, which occurs widely in nature.
See: Sawyer, D. T. Superoxide Chemistry, McGraw-Hill, doi:10.1036/1097-8542.669650