from
The Collaborative International Dictionary of English v.0.48
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}.
[1913 Webster]
2. (Chem.) Native sodium carbonate; natron. [Obs.]
[1913 Webster]
For though thou wash thee with niter, and take thee
much soap, yet thine iniquity is marked before me.
--Jer. ii. 22.
[1913 Webster]
{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.
[1913 Webster]
from
Easton's 1897 Bible Dictionary
Nitre
(Prov. 25:20; R.V. marg., "soda"), properly "natron," a
substance so called because, rising from the bottom of the Lake
Natron in Egypt, it becomes dry and hard in the sun, and is the
soda which effervesces when vinegar is poured on it. It is a
carbonate of soda, not saltpetre, which the word generally
denotes (Jer. 2:22; R.V. "lye").