flam·​ma·​ble | \ ˈfla-mə-bəl How to pronounce flammable (audio) \

Definition of flammable

: capable of being easily ignited and of burning quickly

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Other Words from flammable

flammable noun

Why Inflammable Is Not the Opposite of Flammable

Combustible and incombustible are opposites, but flammable and inflammable are synonyms. How can that be? The in- of incombustible is a common prefix meaning "not," but the in- of inflammable is a different prefix. Inflammable, which dates back to 1605, descends from Latin inflammare ("to inflame"), itself from in- (here meaning "in" or "into") plus flammare ("to flame"). Flammable also comes from flammare but didn't enter English until 1813. 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.

Examples of flammable in a Sentence

avoid wearing loose flammable clothing when using the blowtorch

Recent Examples on the Web

The flames caught the bottle of flammable liquid, setting the plastic bottle on fire. BostonGlobe.com, "POLICE BLOTTER," 13 June 2019 Fire investigators determined the blaze was caused when a vehicle crashed into the structure and ignited the combustible and flammable fluids inside, FOX 13 reported. Lucia I. Suarez Sang, Fox News, "Fiery hit-and-run crash causes $800G in damage, police say," 24 Sep. 2018 Flannelette, on the other hand, is soft, fluffy, made from plant fiber and instantly flammable. Serah-marie Mcmahon, Teen Vogue, "This New Book Is All About the Dark (And Sometimes Bloody) History of Fashion," 12 Apr. 2019 Think: long pants, long sleeves, and items made out of leather or natural fibers like cotton and wool instead of more flammable synthetics. Carolyn L. Todd, SELF, "10 Tips on How to Survive a Plane Crash (Although They're Really Rare)," 13 Oct. 2018 R-152a is an extremely flammable hydrocarbon gas, just as propane is a hydrocarbon. Matthew Jancer, Popular Mechanics, "Everything You Should Know About Fixing Your Car's A/C," 11 Sep. 2018 Harvesting these stalwarts can actually increase fire risks as more flammable vegetation accumulates. Umair Irfan, Vox, "Ryan Zinke’s claim that “environmental terrorists” are to blame for wildfires, explained," 17 Aug. 2018 Lithium ions move from one side to the other, helped by highly flammable chemicals in the middle called electrolytes. Angela Chen, The Verge, "The best solution for making batteries safer might be the most boring one," 13 Aug. 2018 Safety is naturally a critical part of any aircraft, especially one carrying people, so replacing flammable material is obviously desirable. Joe Pappalardo, Popular Mechanics, "New Lithium Metal Batteries Can Power Drones for Longer (and It Could Change Everything)," 16 Apr. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'flammable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of flammable

1813, in the meaning defined above

History and Etymology for flammable

Latin flammare to flame, set on fire, from flamma

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Statistics for flammable

Last Updated

22 Jun 2019

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Time Traveler for flammable

The first known use of flammable was in 1813

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More Definitions for flammable



English Language Learners Definition of flammable

: capable of being set on fire and of burning quickly


flam·​ma·​ble | \ ˈfla-mə-bəl How to pronounce flammable (audio) \

Kids Definition of flammable

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

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More from Merriam-Webster on flammable

Thesaurus: All synonyms and antonyms for flammable

Spanish Central: Translation of flammable

Nglish: Translation of flammable for Spanish Speakers

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