
1) French word used in English 2) Niter 3) Nitrate 4) Nitre 5) Potassium nitrate 6) Saltpeter
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1) Niter 2) Nitre 3) Saltpeter
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• (n.) Potassium nitrate; niter; a white crystalline substance, KNO3, having a cooling saline taste, obtained by leaching from certain soils in which it is produced by the process of nitrification (see Nitrification, 2). It is a strong oxidizer, is the chief constituent of gunpowder, and is also used as an antiseptic in curing meat, and in med...
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http://thinkexist.com/dictionary/meaning/saltpetre/

any of three naturally occurring nitrates, distinguished as (1) ordinary saltpetre, or potassium nitrate, KNO3; (2) Chile saltpetre, cubic nitre, or ... [7 related articles]
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http://www.britannica.com/eb/a-z/s/17

<chemistry> Potassium nitrate; niter, a white crystalline substance, KNO3, having a cooling saline taste, obtained by leaching from certain soils in which it is produced by the process of nitrification (see Nitrification, 2). It is a strong oxidizer, is the chief constituent of gunpowder, and is also used as an antiseptic in curing meat, and ...
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http://www.encyclo.co.uk/local/20973

Saltpetre is a popular name for potassium nitrate.
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http://www.probertencyclopaedia.com/browse/GS.HTM

saltpetre A crust similar to salt that forms on rocks. Related 'stone, rock' word families: lapid-; litho-; saxi-; stele-.
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http://www.wordinfo.info/words/index/info/view_unit/1620/4

Compound used in making gunpowder (from about 1500). It occurs naturally, being deposited during dry periods in places with warm climates, such as India
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https://www.encyclo.co.uk/local/21221
No exact match found.