Chile saltpeter

Niter \Ni"ter\, Nitre \Ni"tre\, n. [F. nitre, L. nitrum native
   soda, natron, Gr. ?; cf. Ar. nit[=u]n, natr[=u]n natron. Cf.
   {Natron}.]
   1. (Chem.) A white crystalline semitransparent salt;
      potassium nitrate; saltpeter. See {Saltpeter}.
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   2. (Chem.) Native sodium carbonate; natron. [Obs.]
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            For though thou wash thee with niter, and take thee
            much soap, yet thine iniquity is marked before me.
                                                  --Jer. ii. 22.
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   {Cubic niter}, a deliquescent salt, sodium nitrate, found as
      a native incrustation, like niter, in Peru and Chile,
      whence it is known also as {Chile saltpeter}.

   {Niter bush} (Bot.), a genus ({Nitraria}) of thorny shrubs
      bearing edible berries, and growing in the saline plains
      of Asia and Northern Africa.
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