sodium hydroxide

American  

noun

Chemistry.

1. a white, deliquescent, water-soluble solid, NaOH, usually in the form of lumps, sticks, chips, or pellets, that upon solution in water generates heat: used chiefly in the manufacture of other chemicals, rayon, film, soap, as a laboratory reagent, and in medicine as a caustic.

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sodium hydroxide British  

noun

1. Also called: caustic soda.  a white deliquescent strongly alkaline solid used in the manufacture of rayon, paper, aluminium, soap, and sodium compounds. Formula: NaOH See also lye

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sodium hydroxide Scientific  

1. A white, corrosive, solid compound that absorbs water and carbon dioxide from the atmosphere and forms lye when in solution. Sodium hydroxide is toxic and strongly alkaline and is used to make chemicals and soaps and to refine petroleum. Chemical formula: NaOH.

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Etymology

Origin of sodium hydroxide

First recorded in 1880–85

Compare meaning

How does sodium-hydroxide compare to similar and commonly confused words? Explore the most common comparisons:

• potassium hydroxide vs. sodium hydroxide

Example Sentences

See Examples For:

sodium hydroxide

White liquor is an alkaline chemical containing sodium hydroxide and sodium sulfide.

From BBC ● May 26, 2026

Monday in the area of Low Line and Magnolia roads in Morgan County and the nine derailed cars contained dry cement, calcium chloride and sodium hydroxide, according to CSX and county officials.

From Seattle Times ● Feb. 13, 2024

The team treated the fruiting bodies of enoki mushrooms and the inedible reishi mushrooms with sodium hydroxide and hydrogen peroxide.

From Science Daily ● Jan. 8, 2024

He is leading a project to study the effects of pouring tons of alkaline sodium hydroxide into the ocean off the New England coast.

From Science Magazine ● Nov. 30, 2023

Add 50 to 100 cc. hot, neutral alcohol, and titrate with N/2, N/4 or N/10 sodium hydroxide depending on the fatty acid content, using phenolphthalein as indicator.

From Soap-Making Manual A Practical Handbook on the Raw Materials, Their Manipulation, Analysis and Control in the Modern Soap Plant. by Thomssen, E. G.