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 two workers were initially trapped inside the locomotive, and a flammable liquid was leaking into the Big Sandy River, emergency officials said, The Associated Press reported. Julia Jacobo, ABC News, "Crew members escape fiery train after it derails in Kentucky," 13 Feb. 2020 Avoid landscaping using conifers with wood containing flammable waxes, fats or oils. Washington Post, "Extreme weather has gardeners looking for resilient plants," 4 Feb. 2020 A couple years back, someone thought to build a flammable wick into the middle of parachute cord, and this is another useful iteration of that. Tyler Freel, Outdoor Life, "The 10 Best Pieces of Backcountry and Survival Gear from SHOT Show 2020," 3 Feb. 2020 One factory in Iran is making money off of protesters who burn American, British, and Israeli flags and is pumping out thousands of the flammable banners per year. Zachary Halaschak, Washington Examiner, "Iranian factory profits as protesters burn thousands of US and Israeli flags," 30 Jan. 2020 The company filed to take enough precautions to prevent the ignition of flammable vapors. Cameron Knight, Cincinnati.com, "Midwest Ammunition cited by OSHA after employee death," 28 Jan. 2020 Set it on a flat, level surface - not on the carpet and not on anything flammable. Houston Chronicle, "Houston Apartment Association: Weather wintertime in your apartment," 18 Jan. 2020 Highly flammable: California, 15 other states question safety of shipping liquefied natural gas by rail. Taylor Kate Brown, SFChronicle.com, "Bay Briefing: A roof for everyone — by constitutional amendment," 14 Jan. 2020 The underlying reason for the devastation is the exceptionally hot and dry weather, which made the bush more flammable (2019 was Australia’s hottest year on record). The Economist, "A burning question Why was Australia’s government so ill-prepared for the bushfires?," 11 Jan. 2020

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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Time Traveler for flammable

Time Traveler

The first known use of flammable was in 1813

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Statistics for flammable

Last Updated

16 Feb 2020

Cite this Entry

“Flammable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flammable. Accessed 17 Feb. 2020.

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More Definitions for flammable


How to pronounce flammable (audio)

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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