retardant

adjective

re·​tar·​dant ri-ˈtär-dᵊnt 

: serving or tending to retard

a growth-retardant substance

retardant noun

Examples of retardant in a Sentence

Recent Examples on the Web

On Monday, firefighters were working to wash streaks of pink fire retardant off the streets and finish building containment lines around the charred hills between San Clemente and San Juan Capistrano. — Hannah Fry, Los Angeles Times, 20 Oct. 2026

Aerial footage showed aircraft dropping fire retardant over the area. — Chelsea Hylton, CBS News, 16 Oct. 2026

Flame-retardant defense uniforms are often stiff and heavy, but Gore-Tex Labs’ Pyrad fabric technology offers a better option. — Derek Rose, Time, 15 Oct. 2026

That fire was 140 acres on Thursday, with air tankers and helicopters dropping water and retardant to limit its spread. — Paul Rogers, Mercury News, 27 Aug. 2026

Word History

First Known Use

1642, in the meaning defined above

Phrases Containing retardant

• flame-retardant

Rhymes for retardant

• ardent

Kids Definition

retardant

adjective

re·​tar·​dant ri-ˈtärd-ᵊnt 

: serving or tending to retard

flame-retardant fabrics