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

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Other Words from inflammable

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

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 inflammable in a Sentence

some pajamas are made of inflammable material, so be careful

Recent Examples on the Web

The tenants were essentially living on the top of a highly inflammable firetrap, one in which mass evacuation was impossible, as was evidenced when a few of victims filmed their last moments with their phones. Henry Porter, The Hive, "How the Grenfell Tower Fire Became a Metaphor for Britain’s Year from Hell," 16 June 2017 This is because of the inflammable hydrogen used in the Zeppelin. Kurt Chandler,, "Son traces his father's steps through Europe, shares his impressions with the world," 16 June 2017

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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English Language Learners Definition of inflammable

: capable of being set on fire and of burning quickly
: easily excited or angered


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

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More from Merriam-Webster on inflammable

Rhyming Dictionary: Words that rhyme with inflammable

Thesaurus: All synonyms and antonyms for inflammable

Spanish Central: Translation of inflammable

Nglish: Translation of inflammable for Spanish Speakers

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