- any substance capable of reducing the speed of a given reaction.
Origin of retardant
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- a substance that reduces the rate of a chemical reaction
- having a slowing effect
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 retardant
Online Etymology Dictionary, © 2010 Douglas Harper