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Added 10 October 2026

peroxide

/pəˈɹɒksaɪd/ noun

noun Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about peroxide at Wordnik → Where our words come from →

A viscous liquid with strong oxidizing properties; a powerful bleaching agent; also used (in aqueous solutions) as a mild disinfectant and (in strong concentrations) as an oxidant in rocket fuels.
An inorganic compound containing the divalent ion -O-O-.

verb

Bleach with peroxide.
She must peroxide her hair-it looks unnaturally blond

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