retardant

[ ri-tahr-dnt ]
/ rɪˈtɑr dnt /

noun Chemistry.

any substance capable of reducing the speed of a given reaction.

adjective

retarding or tending to retard (usually used in combination): fire-retardant construction materials.

Origin of retardant

First recorded in 1635–45; retard + -ant

Related forms

re·tard·ance, re·tard·an·cy, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for retardance

retardant

/ (rɪˈtɑːdənt) /

noun

a substance that reduces the rate of a chemical reaction

adjective

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