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

Investigators also found broken glass scattered through the home, a shattered microwave, and bleach wipes and spray bottles.

From Los Angeles Times • Mar. 10, 2026

In 2017, they bought a former steel works and an abandoned bleach factory next door for $25 million and started hosting the Mirage in the lot between them.

From The Wall Street Journal • Feb. 27, 2026

"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

Some of the gels were advertised as containing "extreme bleach" and boasted that they were "so strong it's not available to buy in the UK".

From BBC • Oct. 28, 2025

There was Mouschi crouched under a chair, Peter armed with water, powdered bleach and a cloth, and Mr. van Daan trying to calm everyone down.

From "The Diary of a Young Girl" by Anne Frank

Related Words

• lighten