retardant

adjective

re·​tar·​dant ri-ˈtär-dᵊnt How to pronounce retardant (audio)
Synonyms of retardantnext
: serving or tending to retard
a growth-retardant substance
retardant noun

Examples of retardant in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Forest Service officials described an aggressive effort to contain the blaze, with air tankers dropping retardant from above while ground crews and bulldozers worked to build control lines around the wildfire and prevent it from spreading. — Darrell Smith, Sacbee.com, 14 Aug. 2026 They can be equipped with tanks to drop water or fire retardant onto blazes. — Los Angeles Times, 8 Aug. 2026 Videos from the fire zone showed towering smoke plumes rising above trees and neighborhoods as airplane tankers dropped fire retardant on the fast-moving flames. — Jeanine Santucci, USA Today, 4 Aug. 2026 Emergency responders rushed to the scene after the crash, with aerial footage showing firefighters spraying fire retardant on the burning wreckage while thick black smoke rose above the base. — Neetika Walter, Interesting Engineering, 31 July 2026 See All Example Sentences for retardant

Word History

First Known Use

1642, in the meaning defined above

Time Traveler
The first known use of retardant was in 1642

Phrases Containing retardant

Rhymes for retardant

See All Rhymes for retardant

Browse Nearby Words

retardancy
retardant
retardate
See all Nearby Words

Cite this Entry

“Retardant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/retardant. Accessed 20 Aug. 2026.

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Kids Definition

retardant

adjective
re·​tar·​dant ri-ˈtärd-ᵊnt How to pronounce retardant (audio)
: serving or tending to retard
flame-retardant fabrics

More from Merriam-Webster on retardant

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