sodium hydrosulfite

noun

, Chemistry.

1. a white, crystalline, water-soluble powder, Na 2 S 2 O 4 , used as a reducing agent, especially in dyeing, and as a bleach.

Example Sentences

Most of the works is out of doors �which is almost necessary, because Annie uses lye and sodium hydrosulfite, resulting in fumes that make it necessary for her to cover her hair, wear rubber gloves and an apron, and douse herself thoroughly in vinegar at the end of a dyeing day.

From Time Magazine Archive