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1804, formed in English from per- "large amount" + oxide. Peroxide blonde is attested from 1918.
peroxide per·ox·ide (pə-rŏk'sīd')n.
A compound, such as sodium peroxide, that contains a peroxy group and yields hydrogen peroxide when treated with an acid.
A compound containing the group O2. Peroxides are strong oxidizers and are used as industrial bleaches. When any peroxide is combined with an acid, one of the products is hydrogen peroxide.