potassium nitrate

American  

noun

Chemistry.

1. a crystalline compound, KNO 3 , produced by nitrification in soil, and used in gunpowders, fertilizers, and preservatives; saltpeter; niter.

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potassium nitrate British  

noun

1. Also called: saltpetre.   nitre.  a colourless or white crystalline compound used in gunpowders, pyrotechnics, fertilizers, and as a preservative for foods, esp as a curing salt for ham, sausages, etc ( E252 ). Formula: KNO 3

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potassium nitrate Scientific  

1. A transparent, white, crystalline compound and strong oxidizing agent. It is used in gunpowder and fireworks, in making glass, and in fertilizer. Also called saltpeter. Chemical formula: KNO ₃ .

2. See also niter

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Etymology

Origin of potassium nitrate

First recorded in 1880–85

Example Sentences

The analysis focused on 17 individual preservatives, including citric acid, lecithins, total sulfites, ascorbic acid, sodium nitrite, potassium sorbate, sodium erythorbate, sodium ascorbate, potassium metabisulfite, and potassium nitrate.

From Science Daily • Jan. 27, 2026

Black powder, first formulated in China more than a millennium ago, is a mixture of sulphur, carbon and potassium nitrate.

From Washington Times • Aug. 11, 2022

Gunpowder is a mixture of potassium nitrate, sulfur, and charcoal.

From Textbooks • Feb. 14, 2019

There were sacks of explosive precursors, including potassium chloride, red iron oxide and potassium nitrate.

From Salon • Nov. 26, 2018

He could tell just from picking up a toothpaste tube whether it contained potassium nitrate.

From "The House of Hades" by Rick Riordan