peroxide

American  

[puh-rok-sahyd] / pəˈrɒk saɪd /

noun

1. Chemistry.

   1. hydrogen peroxide, H 2 O 2 or H–O–O–H.

   2. a compound containing the bivalent group –O 2 –, derived from hydrogen peroxide, as sodium peroxide, Na 2 O 2 , or dimethyl peroxide, C 3 H 6 O 2 .

   3. the oxide of an element that contains an unusually large amount of oxygen.

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verb (used with object)

peroxided, peroxiding

1. to use peroxide as a bleaching agent on (especially the hair).

peroxide British  

/ pəˈrɒksaɪd /

noun

1. short for hydrogen peroxide, esp when used for bleaching hair

2. any of a class of metallic oxides, such as sodium peroxide, Na 2 O 2 , that contain the divalent ion ^– O-O ^–

3. (not in technical usage) any of certain dioxides, such as manganese peroxide, MnO 2 , that resemble peroxides in their formula but do not contain the ^– O-O ^– ion

4. any of a class of organic compounds whose molecules contain two oxygen atoms bound together. They tend to be explosive

5. (modifier) of, relating to, bleached with, or resembling peroxide

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verb

1. (tr) to bleach (the hair) with peroxide

peroxide Scientific  

/ pə-rŏk′sīd′ /

1. A compound containing the group O ₂. Peroxides are strong oxidizers and are used as industrial bleaches. When any peroxide is combined with an acid, one of the products is hydrogen peroxide.

2. Hydrogen peroxide.

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Other Word Forms

• peroxidic adjective

Etymology

Origin of peroxide

First recorded in 1795–1805; per- + oxide

Example Sentences

The researchers found that the crystals, made from an iron-containing compound called heme, are set in motion by the breakdown of hydrogen peroxide into water and oxygen.

From Science Daily • Mar. 19, 2026

This type of propulsion is well known in aerospace engineering, where hydrogen peroxide is used as a fuel to launch spacecraft, but it had not previously been identified in a biological system.

From Science Daily • Mar. 19, 2026

When the researchers treated stressed skin cells with catalase, a naturally occurring antioxidant enzyme that breaks down hydrogen peroxide, cellular stress levels dropped.

From Science Daily • Jan. 20, 2026

When E. faecalis is present in a wound, the hydrogen peroxide it produces causes oxidative stress in nearby human skin cells.

From Science Daily • Jan. 20, 2026

With a bottle of peroxide and a can of salve I would doctor their wounds.

From "Where the Red Fern Grows" by Wilson Rawls

Related Words

• lighten