What does "niter" mean?

Niter: (Chem.) Native sodium carbonate; natron. [Obs.] For though thou wash thee with niter, and take thee much soap, yet thine iniquity is marked before me. Jer. ii.

Additional senses

  1. 2.Cubic niter, a deliquescent salt, sodium nitrate, found as a native incrustation, like niter, in Peru and Chili, whence it is known also as Chili 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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