sodium thiosulfate


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

called also fixer, hypo

Examples of sodium thiosulfate in a Sentence

Recent Examples on the Web Thanks to this ingredient along with sodium thiosulfate, the shampoo is also a great option for dissolving chlorine left in hair from pool days. ELLE, 24 Aug. 2023 What to Look for in the Best Chlorine Shampoos When searching for the best chlorine shampoos, look for ingredients like apple cider vinegar, ethylene diamine tetra acetic-acid (EDTA), sodium thiosulfate, charcoal, and crystallized vitamin C to effectively remove chlorine. Joseph Cheatham, Men's Health, 17 July 2023 About 40 cows at the Sommariva Bosco farm were successfully saved after being injected with a sodium thiosulfate antidote, Giantin previously told the AFP and the Associated Press. Isabella Fertel, USA TODAY, 16 June 2023 To ensure all chemicals are washed from your hair post-swim, professionals recommend keeping an eye out for shampoos with acids and compounds equipped to dissolve chlorine molecules, like vitamin C, sodium thiosulfate, or apple cider vinegar. Tiffany Dodson,, 18 May 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'sodium thiosulfate.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1885, in the meaning defined above

Time Traveler
The first known use of sodium thiosulfate was in 1885

Dictionary Entries Near sodium thiosulfate

Cite this Entry

“Sodium thiosulfate.” Dictionary, Merriam-Webster, Accessed 21 Jul. 2024.

Kids Definition

sodium thiosulfate

sodium thio·​sul·​fate
: a chemical compound used especially in photography to make images permanent and in bleaching

Medical Definition

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

More from Merriam-Webster on sodium thiosulfate

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!