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

Definition of inflammable

1 : flammable
2 : easily inflamed, excited, or angered : irascible

Other Words from inflammable

inflammability \ in-​ˌfla-​mə-​ˈbi-​lə-​tē How to pronounce inflammable (audio) \ noun
inflammable noun
inflammableness \ in-​ˈfla-​mə-​bəl-​nəs How to pronounce inflammable (audio) \ noun
inflammably \ in-​ˈfla-​mə-​blē How to pronounce inflammable (audio) \ adverb

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.

Examples of inflammable in a Sentence

some pajamas are made of inflammable material, so be careful
Recent Examples on the Web It can be synthesized through a chemical process using acetic anhydride, a high-inflammable and colorless liquid used to make fibers, plastics, pharmaceuticals, dyes, and explosives. Dario Sabaghi, Forbes, 18 Jan. 2022 By the way, the top stories on that January day in 1952 were a White House nomination for Vatican envoy withdrawing amid controversy, and a recall of inflammable sweaters. Brian Stelter, CNN, 13 Jan. 2022 The gas was said to be non-inflammable and non-explosive. Popular Mechanics Editors, Popular Mechanics, 11 Jan. 2022 High levels of methane gas and coal dust, both highly inflammable, make mines hazardous. Washington Post, 26 Nov. 2021 Although civil protection and the response to fires in the area have improved over the years, bureaucratic hurdles aimed at protecting Mediterranean scrubland mean that inflammable vegetation is often not cleared, creating fire hazards, experts say. Gaia Pianigiani, New York Times, 22 Aug. 2021 An artificial strait without nature's currents will reduce the kind of accidents that bedevil ships passing through the Bosphorus's treacherous contours, especially tankers carrying huge amounts of inflammable petrochemicals. Melik Kaylan, Forbes, 17 May 2021 Offshore platforms are notoriously hazardous locations, dense with heavy equipment and handling large quantities of highly inflammable liquids and gases. University Of Houston Energy Fellows, Forbes, 15 Apr. 2021 Each soldier engaged in this form of attack has strapped to his back a tank containing an inflammable liquid under high pressure. Popular Mechanics Editors, Popular Mechanics, 30 Sep. 2020 See More

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

First Known Use of inflammable

1605, in the meaning defined at sense 1

History and Etymology for inflammable

French, from Medieval Latin inflammabilis, from Latin inflammare

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The first known use of inflammable was in 1605

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inflammable air

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Cite this Entry

“Inflammable.” Dictionary, Merriam-Webster, Accessed 24 May. 2022.

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More Definitions for inflammable


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

Kids Definition of inflammable

1 : flammable
2 : easily inflamed : excitable an inflammable temper

More from Merriam-Webster on inflammable

Nglish: Translation of inflammable for Spanish Speakers


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