retardant
Americannoun
adjective
noun
adjective
Other Word Forms
Etymology
Origin of retardant
Explanation
A retardant is anything that prevents something from happening, or inhibits it from growing or spreading. Using a rust retardant on your car, for example, should help keep it from getting rusty. A fire or flame retardant is a type of chemical that stops fire from starting or spreading. Sometimes fire retardants are sprayed or dumped on a fire to put it out, like the foam fire retardant you might spray from a hand-held fire extinguisher onto a grease fire in a kitchen. Retardant comes from the verb retard, "make slow, or make slower."
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Aircraft dropped water and flame retardant from above, while ground crews built firebreaks with equipment ranging from bulldozers to hand tools.
From Science Daily ● Aug. 5, 2026
Planes often fly in a continuous shuttle while retardant is laid along the edges of the fire and ground crews attack the flames directly.
From BBC ● Jul. 27, 2026
Two fixed-wing airplanes arrived on scene rapidly and dropped flame retardant around the perimeter of the blaze, while three helicopters dropped water from above, according to Ventura County Fire spokesperson Andrew Dowd.
From Los Angeles Times ● Jul. 10, 2026
I pay for a private fire department, and we have built-in retardant sprayers.
From The Wall Street Journal ● Jun. 23, 2026
The colorful fire retardant drew Akira’s eye to the front line of the fire, and she saw a group of tiny figures using axes and bulldozers to fight the blaze in the valley.
From "Two Degrees" by Alan Gratz
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
