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

Oxygen bleach stain removers rely on hydrogen peroxide to lift stains and come in liquid or powder form. —Brandee Gruener, Southern Living, 6 Oct. 2025

Try to keep both dry between uses, disinfect the brush head weekly (soaking it in hydrogen peroxide or antibacterial mouthwash will do the trick), and replace your toothbrush every three to four months. —Mary Cornetta, Better Homes & Gardens, 24 Sep. 2025

Formulated without alcohol or hydrogen peroxide, the TheraBreath Whitening Fresh Breath Oral Rinse uses glucose oxidase and enzymes called papain to help break up stains and kill bad-breath-causing bacteria—all without aggravating sensitive teeth and gums. —Sophia Panych, Allure, 16 Sep. 2025

Fatty acids found in oils like sunflower or olive oil are mixed with hydrogen peroxide. —Kurt Knutsson, FOXNews.com, 14 Sep. 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