peroxide

A divalent radical or anion containing two oxygen atoms linked by a covalent bond; any substance containing this group yields hydrogen peroxide when treated with an acid.

Hydrogen peroxide, especially when in an aqueous solution used as a bleach.

Any compound containing the functional group R-O-O-R'.

Thus far, Dr. Petrakis said, he had found that in women with […] extractable breast fluid, the amount of lipid peroxides in the fluid was on the average seven times higher in Caucasian women than in women of Chinese de[s]cent. In addition, women with cystic breast disease, who face a higher than usual risk of breast cancer, appear to have more peroxides in their breast fluid than women with normal breasts.

The O–O bond in benzoyl peroxide and the C–N bonds in AIBN homolyze under thermal or photochemical conditions.

To treat (something) with hydrogen peroxide, especially hair in order to bleach it.