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

"We think that the breakdown of hydrogen peroxide likely makes an important contribution to reducing cellular stress," Sigala says.

From Science Daily • Mar. 19, 2026

Experiments confirmed that hydrogen peroxide alone could cause isolated crystals to spin, even outside the parasite.

From Science Daily • Mar. 19, 2026

Compared with normal tissue, cancer cells tend to be more acidic and contain higher levels of hydrogen peroxide.

From Science Daily • Mar. 1, 2026

These altered bacteria produced much less hydrogen peroxide and were no longer able to block wound healing.

From Science Daily • Jan. 20, 2026

I burst through the doors, the smell of iodine and peroxide hits me, but all I have time to see is two men wearing surgical caps and a woman in green huddling over a gurney.

From "The Kite Runner" by Khaled Hosseini

Related Words

• lighten