sodium hydroxide

noun

|Updated on: 31 May 2018

Definition of sodium hydroxide

: a white brittle solid NaOH that is a strong caustic base used especially in making soap, rayon, and paper

Recent Examples of sodium hydroxide from the Web

Using a main ingredient of sodium hydroxide, lithium hydroxide, potassium hydroxide, or guanidine hydroxide, chemical relaxers break and restructure the bonds in curly hair so that the hair becomes weaker and straight.

— ashley weatherford, The Cut, "The Everything Guide to Keratin Treatments," 15 May 2018
If the alkali is sodium hydroxide, the result is a hard soap, relatively difficult to dissolve.

— c. claiborne ray, New York Times, "In Your Bathroom, the Scum of the Earth," 6 Apr. 2018
Their simple, two-step process starts with boiling wood in a solution of sodium hydroxide (NaOH) and sodium sulfite (Na2SO3), a chemical treatment similar to the first step in creating the wood pulp used to make paper.

— sid perkins, Scientific American, "Stronger Than Steel, Able to Stop a Speeding Bullet—It’s Super Wood!," 7 Feb. 2018
One thousand pounds of sodium hydroxide, also known as lye, leaked from the tank, according to the response center report.

— sara sneath, NOLA.com, "37 chemical releases reported in St. James Parish over 14 month period," 27 Mar. 2018
Skyscrapers of the future could even be built from wood. The process starts by soaking wood in a bath of sodium hydroxide and sodium sulfate.

— marissa fessenden, Smithsonian, "New Super Wood Beats Metals in Feats of Strength," 10 Feb. 2018
Maine’s Department of Environmental Protection website says the plant had several owners from 1967 through 2000 and produced chlorine, sodium hydroxide, chlorine bleach, hydrochloric acid and the pesticide chloropicrin.

— Washington Post, "Firm drawing up options for mercury cleanup on Maine river," 1 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sodium hydroxide.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of sodium hydroxide

1885

in the meaning defined above

See Words from the same year

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Medical Dictionary

sodium hydroxide

noun

medical Definition of sodium hydroxide

: a white brittle deliquescent solid NaOH that dissolves readily in water to form a strongly alkaline and caustic solution and that is used in pharmacy as an alkalizing agent — called also caustic soda