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

See Examples For:

bleaching powder

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

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

Then place a piece of calico in the water containing the bleaching powder.

From Textiles For Commercial, Industrial, and Domestic Arts Schools; Also Adapted to Those Engaged in Wholesale and Retail Dry Goods, Wool, Cotton, and Dressmaker's Trades by William H. (William Henry) Dooley

Chemical disinfectants in milk: bleaching powder, 81; corrosive sublimate, 81; formalin, 80; sulfur, 80; whitewash, 81; vitriol, 81.

From Outlines of Dairy Bacteriology, 8th edition A Concise Manual for the Use of Students in Dairying by H. L. (Harry Luman) Russell