fireproof

1 of 2

adjective

fire·​proof ˈfī(-ə)r-ˌprüf 

: proof against or resistant to fire

fireproof

2 of 2

verb

fireproofed; fireproofing; fireproofs

transitive verb

: to make fireproof

Synonyms

Adjective

• noncombustible
• incombustible
• nonflammable

Examples of fireproof in a Sentence

Adjective

remember to store valuable papers in a fireproof box

Verb

The building was not fireproofed.

Recent Examples on the Web

Adjective

In 2021, firefighters wrapped trees with fireproof aluminum blankets in the famous Giant Forest in Sequoia National Park, home to five of Earth’s 10 largest trees, including the biggest of them all, the General Sherman Tree. —Ethan Baron, Mercury News, 10 Sep. 2025

Its first offices consisted of two rooms and a fireproof vault in the old courthouse (built in 1874) in Washington. —Arkansas Online, 23 Aug. 2025

Verb

Antimony is an indispensable ingredient in ammunition, fireproofing military equipment, nuclear systems, and much more. —Lee Habeeb, MSNBC Newsweek, 3 Apr. 2025

Because of their supply of unfree labor to fight fires, Southern leaders felt little need to fireproof their cities, or adopt the innovations in firefighting made possible by new technologies. —Justin Hawkins / Made By History, TIME, 31 Jan. 2025

Word History

First Known Use

Adjective

1610, in the meaning defined above

Verb

1841, in the meaning defined above

Rhymes for fireproof

• bulletproof
• waterproof
• weatherproof
• aloof
• behoof
• disproof
• flameproof
• foolproof
• greaseproof
• leakproof
• reproof
• soundproof

Kids Definition

fireproof

1 of 2 adjective

fire·​proof -ˈprüf 

: not easily burned : made safe against fire

fireproof

2 of 2 verb

: to make fireproof