noun
also ni·tre ˈnīd.ə(r), -ītə-
( -s )
Etymology: Middle English nitre natron, from Middle French, from Latin nitrum, from Greek nitron, from Egyptian nṯry
1. usually nitre , obsolete : natron
2.
a. : potassium nitrate especially occurring naturally (as in desert deposits in northern Chile)
b. : sodium nitrate ; especially : chile saltpeter
c. archaic : nitrate 1
3. usually nitre , obsolete : a supposed nitrous substance or element occurring especially diffused through the air
4. usually nitre : ethyl nitrite
spirit of niter
— compare ethyl nitrite spirit
5. : sugar sand