来自古法语 salpetre,硝石，硝酸钾，来自拉丁语 sal petrae,石头上的盐，来自 sal,盐，词源同 salt,petra,石头，词源同 petrous,petrol.因这种物质形如盐在石头上的结晶体而得名。
英文词源
saltpeter (n.)
"potassium nitrate," c. 1500, earlier salpetre (early 14c.), from Old French salpetre, from Medieval Latin sal petrae "salt of rock," from Latin sal "salt" (see salt (n.)) + petra "rock, stone" (see petrous). So called because it looks like salt encrusted on rock.