natron
noun
na·tron ˈnā-ˌträn 
-trən
-trən : a hydrous native sodium carbonate used in ancient times in embalming, in ceramic pastes, and as a cleansing agent
Example Sentences
Recent Examples on the Web Lake Natron gets its name from the naturally occurring mixture of sodium carbonates called natron. 
Rachael Lallensack, Smithsonian Magazine, 29 Oct. 2021 If so, this would be the first evidence for this practice being applied to a snake, although historical texts suggest a similar practice for the Apis bull, involving placing myrrh and natron under the tongue to slow down decomposition. Jennifer Ouellette, Ars Technica, 21 Aug. 2020 There was also evidence of the mouth opening being filled with resin (most likely natron) to render the snake harmless. Jennifer Ouellette, Ars Technica, 21 Aug. 2020 After removing the body’s internal organs, priests would use natron, a naturally occurring salt, to dry it out. National Geographic, 10 Dec. 2019 The proportion of magnesia in inlays and window glass from Samarra’s palaces suggests plant ash, rather than natron, as the source of sodium carbonate in the glassmaking process. Kiona N. Smith, Ars Technica, 31 Aug. 2018
Rachael Lallensack, Smithsonian Magazine, 29 Oct. 2021 If so, this would be the first evidence for this practice being applied to a snake, although historical texts suggest a similar practice for the Apis bull, involving placing myrrh and natron under the tongue to slow down decomposition. Jennifer Ouellette, Ars Technica, 21 Aug. 2020 There was also evidence of the mouth opening being filled with resin (most likely natron) to render the snake harmless. Jennifer Ouellette, Ars Technica, 21 Aug. 2020 After removing the body’s internal organs, priests would use natron, a naturally occurring salt, to dry it out. National Geographic, 10 Dec. 2019 The proportion of magnesia in inlays and window glass from Samarra’s palaces suggests plant ash, rather than natron, as the source of sodium carbonate in the glassmaking process. Kiona N. Smith, Ars Technica, 31 Aug. 2018 Word History
Etymology
borrowed from French naitron, natron, borrowed (by uncertain mediation) from Arabic naṭrūn, borrowed from Greek nítron niter
First Known Use
1684, in the meaning defined above