flammable

adjective

flam·​ma·​ble ˈfla-mə-bəl 

: capable of being easily ignited and of burning quickly

flammable noun

Did you know?

Why Inflammable Is Not the Opposite of Flammable

Combustible and incombustible are opposites but flammable and inflammable are synonyms. Why? The in- of incombustible is a common prefix meaning "not," but the in- of inflammable is a different prefix. Inflammable comes from Latin inflammare ("to inflame"), itself from in- (here meaning "in" or "into") plus flammare ("to flame"). Flammable also comes from flammare. In the early 20th century, firefighters worried that people might think inflammable meant "not able to catch fire," so they adopted flammable and nonflammable as official safety labels and encouraged their use to prevent confusion. In general use, flammable is now the preferred term for describing things that can catch fire, but inflammable is still occasionally used with that meaning as well.

Synonyms

• burnable
• combustible
• combustive
• fiery
• ignitable
• ignitible
• inflammable
• touchy

Examples of flammable in a Sentence

avoid wearing loose flammable clothing when using the blowtorch

Recent Examples on the Web

Boeing delayed Starliner's first crewed flight last year, after company officials realized that adhesive tape used on hundreds of yards of wiring was potentially flammable, and the capsule’s three parachutes were connected with lines that appeared to be weaker than expected. —Geoff Brumfiel, NPR, 1 June 2024

The result now is a landscape of dense forests dominated by conifers, which are extremely flammable. —Norimitsu Onishi, New York Times, 29 May 2024

The report also called out Shein suppliers for safety hazards, including for not enforcing a ban on smoking, which could cause a fire because textiles are flammable. —Marco Quiroz-Gutierrez, Fortune, 13 May 2024

Lithium-ion batteries are flammable, and while operators have taken steps to reduce fire risk, some communities oppose projects in their backyards. —Brad Plumer, New York Times, 6 May 2024

Word History

Etymology

Latin flammare to flame, set on fire, from flamma

First Known Use

1813, in the meaning defined above

Kids Definition

flammable

adjective

flam·​ma·​ble ˈflam-ə-bəl 

: capable of being easily set on fire and of burning rapidly

a flammable liquid

flammability

ˌflam-ə-ˈbil-ət-ē

noun

flammable noun