flammable
Americanadjective
adjective
Usage
Flammable and inflammable are interchangeable when used of the properties of materials. Flammable is, however, often preferred for warning labels as there is less likelihood of misunderstanding ( inflammable being sometimes taken to mean not flammable ). Inflammable is preferred in figurative contexts: this could prove to be an inflammable situation
Commonly Confused
See inflammable.
Other Word Forms
Etymology
Origin of flammable
First recorded in 1805–15; from Latin flammā(re) “to set on fire” + -ble
Explanation
Be careful with matches around gasoline, dry grass, and old wood because they are all very flammable and might catch on fire. Flammable is a pretty straightforward word with one odd fact about it. The word, inflammable, which sounds like the opposite of flammable, actually means the same thing — easily catching on fire. If you want to say that something won't catch fire easily, use fireproof and you'll be sure to be right.
Vocabulary lists containing flammable
Power Suffix: -able
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
List 6
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Hatchet
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
A statewide Cal Fire program risks making fires worse by removing native chaparral and allowing the spread of more flammable grasses, a court ruled.
From Los Angeles Times ● Oct. 17, 2026
A faulty valve on a CalMac ferry led to a sudden and uncontrolled release of highly flammable methane gas last summer, BBC Scotland News has learned.
From BBC ● Sep. 8, 2026
"When the water is drained, the peat dries and becomes flammable."
From Barron's ● Sep. 6, 2026
The fires are difficult to extinguish because many occurred on peatlands, a wetland ecosystem with layers of partially decomposed organic materials that become flammable when dry.
From Barron's ● Sep. 5, 2026
“A candle. You want to light a candle in here? In a room filled with very dry, flammable things?”
From "Night Owls" by A.R. Vishny
Random Word
Spin the wheel and learn a new word!
Get a wordDefinitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
