hydrogen peroxide

noun

: an unstable compound H₂O₂ used especially as an oxidizing and bleaching agent, an antiseptic, and a propellant

Examples of hydrogen peroxide in a Sentence

Recent Examples on the Web

Rinse your cloth often in warm water and dampen again with hydrogen peroxide. —Mary Marlowe Leverette, Southern Living, 14 Jan. 2026

Borax and Water Similar to hydrogen peroxide, Borax is effective against mold and mildew and is excellent at removing soap scum. —Mary Cornetta, Better Homes & Gardens, 14 Jan. 2026

For less intensive tasks like dusting or cleaning crumbs off the counter, consider avoiding strong disinfectants like bleach, hydrogen peroxide and a category of chemicals called quaternary ammonium compounds that can often be found in disinfectants, hair products and fabric softeners. —Katelyn Richard, The Conversation, 9 Jan. 2026

That’s because contact solution that contains hydrogen peroxide—an ingredient found in many explosives—isn’t allowed on planes. —Katie Jackson, Travel + Leisure, 28 Dec. 2025

Word History

First Known Use

1872, in the meaning defined above

Rhymes for hydrogen peroxide

• aminoglycoside
• chlordiazepoxide
• dimethylformamide
• oligosaccharide
• paraformaldehyde
• polynucleotide
• ribonucleotide
• abide
• allied
• applied
• aside
• astride

Kids Definition

hydrogen peroxide

noun

: an unstable liquid compound containing hydrogen and oxygen and used especially for bleaching and as an antiseptic

Medical Definition

hydrogen peroxide

noun

: an unstable compound H₂O₂ used especially as an oxidizing and bleaching agent and as an antiseptic