potassium hydroxide

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A caustic white deliquescent solid, KOH, used as a bleach and in the manufacture of soaps, dyes, alkaline batteries, and many potassium compounds.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun inorganic chemistry The alkaline base KOH, once known as caustic potash; it has a number of industrial uses, including the manufacture of bleach

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a potassium compound often used in agriculture and industry