niter

/ˈnaɪtər/
noun
  1. A white or gray mineral substance (potassium nitrate) used in making gunpowder, fertilizers, and as a food preservative.
    • Farmers sometimes use niter as a natural source of nitrogen for their crops.
    • In the past, niter was mined from caves and used to preserve meat.
    • The old recipe for gunpowder required sulfur, charcoal, and niter.
Synonyms
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