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Rochelle salt

noun Chemistry, Pharmacology.
  1. a colorless or white, water-soluble solid, KNaC4H4O6⋅4H2O, used in silvering mirrors, in the manufacture of Seidlitz powders and baking powder, and in medicine as a laxative.

Origin of Rochelle salt

First recorded in 1745–55; after La Rochelle
Also called potassium sodium tartrate.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for potassium sodium tartrate

Rochelle salt

noun
  1. a white crystalline double salt, sodium potassium tartrate, used in Seidlitz powder. Formula: KNaC 4 H 4 O 6 .4H 2 O

Word Origin for Rochelle salt

C18: named after La Rochelle, French port
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
potassium sodium tartrate in Medicine

Rochelle salt

[rə-shĕl′, rō-]
n.
  1. potassium sodium tartrate
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.