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

Last month, the reflecting pool turned from blue to green days after the renovation was complete, and contractors were seen pouring bottles of hydrogen peroxide into the pool in an attempt to kill the algae. — Philip Wang, Time, 6 July 2026

Use baking soda or hydrogen peroxide for safe, effective grout cleaning without damage. — Daley Quinn, Southern Living, 5 July 2026

Hospitals are also in urgent need of first-aid and medical supplies like gauze, alcohol, hydrogen peroxide, and over-the-counter medications. — Rachel Chang, Travel + Leisure, 2 July 2026

The chemical compound can slowly break down when exposed to hydrogen peroxide, which in turn would create oxygen. — Mack Degeurin, Popular Science, 1 July 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