calcium oxide

American  

[kal-see-uhm ahk-sahyd] / ˈkæl si əm ˈɑk saɪd /

noun

1. Chemistry. Also called quicklime. the compound CaO, a caustic white solid that, when converted to slaked lime, is used especially in the manufacture of mortars, plasters, and other cement-based materials.

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calcium oxide British  

noun

1. Also called: lime.   quicklime.   calx.   burnt lime.   calcined lime.   fluxing lime.  a white crystalline base used in the production of calcium hydroxide and bleaching powder and in the manufacture of glass, paper, and steel. Formula: CaO

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calcium oxide Scientific  

1. A white solid compound that has a very high melting point and reacts with water to form calcium hydroxide. It is often prepared commercially by heating limestone. Calcium oxide is used as an alkali for treating acidic soils and in manufacturing steel, paper, and glass, and it is the main component of lime. Chemical formula: CaO.

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Example Sentences

Take quicklime, otherwise known as calcium oxide, and just add water.

From The Wall Street Journal • Mar. 27, 2026

The path is a relic of an earlier era, when a railroad cut through the area and a brick furnace raged along the Stillaguamish River, converting limestone into calcium oxide.

From Seattle Times • May 16, 2024

The cost of carbon capture using calcium oxide derived from limestone was estimated at between 230 and 835 dollars.

From Science Daily • Mar. 4, 2024

Lime is a white caustic powdery substance comprised of calcium oxide, made by heating limestone.

From Reuters • Jan. 9, 2023

When the calcium oxide has softened the delicate inner skin, it’s peeled off slowly and carefully.

From "I Am Not Your Perfect Mexican Daughter" by Erika L. Sánchez