saltpeter, saltpetre

(salt′pēt′ĕr)

[L. sal petrae, salt of rock]
A common name for potassium nitrate.
CAS # 7757-79-1

Chile saltpeter

A common name for sodium nitrate, NaNO3; a crystalline powder, saline in taste and soluble in water.
CAS # 7631-99-4