hydroquinone

American  

[hahy-droh-kwi-nohn, -druh-kwin-ohn] / ˌhaɪ droʊ kwɪˈnoʊn, -drəˈkwɪn oʊn /

noun

Chemistry.

1. a white, crystalline compound, C 6 H 6 O 2 , formed by the reduction of quinone: used chiefly in photography and to inhibit autoxidation reactions.

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hydroquinone British  

/ ˌhaɪdrəʊˈkwɪnɒl, ˌhaɪdrəʊkwɪˈnəʊn /

noun

1. Also called: quinol.  a white crystalline soluble phenol used as a photographic developer; 1,4-dihydroxybenzene. Formula: C 6 H 4 (OH) 2

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Etymology

Origin of hydroquinone

First recorded in 1860–65; hydro- ¹ + quinone

Example Sentences

Other sellers admitted using regulated ingredients such as kojic acid, hydroquinone and a powerful antioxidant, glutathione, which may cause rashes and other side-effects.

From BBC • Mar. 23, 2025

The FDA said it has received reports of serious side effects, including rashes and facial swelling, from skin-lightening products containing hydroquinone.

From Washington Post • Apr. 19, 2022

Gould has seen the biggest improvement in her skin from hydroquinone but is currently taking a three-month break from it.

From Washington Post • Jun. 20, 2021

If you’re not nursing, you can also use creams containing hydroquinone, or topical retinoids like Retin-A, to treat melasma after you give birth, Dr. Alexis said.

From New York Times • Jul. 30, 2019

Now hydroquinone when dissolved in alkali also acts as a reducing agent, and in this we have the first application of a true coal-tar product as a photographic developer.

From Coal and What We Get from It by Meldola, Raphael