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

If there is mold in your humidifier, it should be deep cleaned with either chlorine bleach or hydrogen peroxide—never both together. —Mary Marlowe Leverette, The Spruce, 25 Feb. 2026

Fill your spray bottle with equal parts warm water and hydrogen peroxide. —Ashlyn Needham, Southern Living, 19 Feb. 2026

For that, Astuguevieille chose to work with hydrogen peroxide. —Jennifer Weil, Footwear News, 16 Feb. 2026

Suitable sanitizers are water with 10% bleach solution, hydrogen peroxide, or rubbing alcohol. —Lauren Landers, Better Homes & Gardens, 2 Feb. 2026

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