sodium thiosulfate


Definition of sodium thiosulfate

: a hygroscopic crystalline salt Na2S2O3 used especially as a photographic fixing agent and a reducing or bleaching agent

called also fixer, hypo

First Known Use of sodium thiosulfate

1885, in the meaning defined above

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The first known use of sodium thiosulfate was in 1885

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Cite this Entry

“Sodium thiosulfate.” Dictionary, Merriam-Webster, Accessed 15 Jan. 2021.

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sodium thiosulfate


Medical Definition of sodium thiosulfate

: a hygroscopic crystalline salt Na2O3S2 that is used as a fixing agent in photography, as a reducing agent and bleaching agent, in chemical analysis for the titration of iodine, and in medicine as an antidote in poisoning especially by cyanides and as an antifungal agent

called also hypo, sodium hyposulfite

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