A white crystalline compound, Na2S2O3, often prepared as a pentahydrate, used as a photographic fixing agent, as a bleach and antichlor, as an antidote for cyanide poisoning, and as an antifungal agent. Also called hypo1, hyposulfite, sodium hyposulfite.
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.