[ kal-uh-mel, -muh l ]
/ ˈkæl əˌmɛl, -məl /

noun Pharmacology.

a white, tasteless powder, Hg2Cl2, used chiefly as a purgative and fungicide.

Origin of calomel

1670–80; < New Latin calomelas coined from Greek kaló(s) fair + mélas black; allegedly so called because its original preparation involved turning black powder into white
Also called mercurous chloride. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for calomel

British Dictionary definitions for calomel


/ (ˈkæləˌmɛl, -məl) /


a colourless tasteless powder consisting chiefly of mercurous chloride, used medicinally, esp as a cathartic. Formula: Hg 2 Cl 2

Word Origin for calomel

C17: perhaps from New Latin calomelas (unattested), literally: beautiful black (perhaps so named because it was originally sublimed from a black mixture of mercury and mercuric chloride), from Greek kalos beautiful + melas black
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

Word Origin and History for calomel



old name for mercurous chloride, 1670s, from French calomel, supposedly (Littré) from Greek kalos "fair" + melas "black;" but as the powder is yellowish-white this seems difficult. "It is perhaps of significance that the salt is blackened by ammonia and alkalis" [Flood].

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for calomel


[ kălə-mĕl′, -məl ]


A colorless, white or brown tasteless compound used as a purgative and an insecticide.mercurous chloride
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.