bleaching powder

American  

noun

Chemistry.

1. a white powder that decomposes on contact with water and has the characteristic odor of gaseous chlorine: regarded, when dry, as a mixed calcium hypochlorite-chloride, used as a commercial bleach for wood pulp, textiles, oils, and soaps, and in laundering as a decolorizer and disinfectant.

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bleaching powder British  

noun

1. Also called: chloride of lime.   chlorinated lime.  a white powder with the odour of chlorine, consisting of chlorinated calcium hydroxide with an approximate formula CaCl(OCl).4H 2 O. It is used in solution as a bleaching agent and disinfectant

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Etymology

Origin of bleaching powder

First recorded in 1850–55

Example Sentences

According to eyewitnesses, the chemical warehouse stored bleaching powder, plastic and hydrogen peroxide, all of which can intensify fires.

From BBC • Oct. 14, 2025

Victims of mustard gas must have their clothes carefully removed, must be "decontaminated" with soap, clean water and sodium bicarbonate, rubbed with a paste of bleaching powder and water, successful antidote for the oily gas.

From Time Magazine Archive

Both patents are based on the same discovery �that wool becomes unshrinkable when soaked in tertiary amyl or butyl hypochlorite, chemicals related to bleaching powder.

From Time Magazine Archive

It is the ordinary bleaching powder of commerce and is quite unstable, hence old preparations, unless sealed, are of little value.

From Special Report on Diseases of Cattle by United States. Bureau of Animal Industry

After a contagious disease, articles may be soaked in water containing a little bleaching powder and a few drops of carbolic acid, followed by thorough rinsing and bleaching in the sun.

From Human Foods and Their Nutritive Value by Snyder, Harry