bleach

American  

[bleech] / blitʃ /

verb (used with object)

1. to make whiter or lighter in color, such as by exposure to sunlight or a chemical agent; remove the color from.

   Do you think she bleaches her hair?

2. to cause (coral) to undergo a loss of color that indicates declining health: caused by a loss of the algae that normally live symbiotically in the coral’s tissues.

   In sufficient concentrations, the chemicals in certain sunscreens can bleach coral.

3. Photography. to convert (the silver image of a negative or print) to a silver halide, either to remove the image or to change its tone.

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verb (used without object)

1. to become whiter or lighter in color.

   The grass in the fields gradually bleached as winter approached, leaving the landscape pale and drab.

2. (of coral) to undergo a loss of color that indicates declining health: caused by a loss of the algae that normally live symbiotically in the coral’s tissues.

   Coral reefs are bleaching due to ocean pollution and rising sea temperatures.

noun

1. a bleaching agent.

2. an act of bleaching.

3. degree of paleness achieved in bleaching.

bleach British  

/ bliːtʃ /

verb

1. to make or become white or colourless, as by exposure to sunlight, by the action of chemical agents, etc

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noun

1. a bleaching agent

2. the degree of whiteness resulting from bleaching

3. the act of bleaching

bleach Scientific  

/ blēch /

1. A chemical agent used to whiten or remove color from textiles, paper, food, and other substances and materials. Chlorine, sodium hypochlorite, and hydrogen peroxide are bleaches. Bleaches remove color by oxidation or reduction.

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Related Words

See whiten.

Other Word Forms

• bleachability noun
• bleachable adjective
• bleacher noun
• half-bleached adjective
• nonbleach noun
• overbleach verb
• rebleach verb
• semibleached adjective
• unbleached adjective
• unbleaching adjective

Etymology

Origin of bleach

First recorded before 1050; Middle English blechen, Old English blǣcean, derivative of blāc “pale”; cognate with Old Norse bleikja, Old High German bleichēn

Explanation

To bleach is to whiten, or to strip of color. After many summers of use, the sun will bleach your favorite beach towel. You might bleach your white laundry, or bleach your dark brown hair until it's pale blonde. In both cases, you use bleach, a strong chemical solution that can often be found in laundry rooms and hair salons. The Old English root word is blæcan, "bleach" or "whiten," from a Germanic source it curiously shares with the word black.

Example Sentences

"People think we only get missiles and shelters. But we have holidays too. Taking photos, drinking mulled wine, eating tasty food, it's nice to switch," said Ovchinnikova, 25 and with bleach blond hair.

From Barron's • Dec. 23, 2025

“They’re getting that good California sun and are all bleach blonde,” said Jessica West, an environmental scientist with the California Department of Fish and Wildlife.

From The Wall Street Journal • Nov. 17, 2025

You need some real heavy duty bleach for that.

From Salon • Aug. 22, 2025

The 5-acre site is now home to workers in protective gear who are organizing potentially hazardous household items — which can include paint, bleach, asbestos and lithium-ion batteries — that cannot be sent to landfills.

From Los Angeles Times • Jan. 30, 2025

There’s a whiff of the bleach that is in our Mercury Home, but mixed with fried oil and what I used to call eau de cafeteria when I still ate lunch at school.

From "Internment" by Samira Ahmed

Related Words

• lighten