Origin and Etymology of saltpeter
Middle English salt petre, alteration of salpetre, from Medieval Latin sal petrae, literally, salt of the rock
First Known Use: 14th century
SALTPETER Defined for English Language Learners
Definition of saltpeter for English Language Learners
: a white powder that exists naturally in some soils and that is used especially as a fertilizer, in medicine, and to make gunpowder
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