Dictionary.com
Thesaurus.com
Synonyms

combustible

American  
[kuhm-buhs-tuh-buhl] / kəmˈbʌs tə bəl /

adjective

  1. capable of catching fire and burning; inflammable; flammable.

    Gasoline vapor is highly combustible.

  2. easily excited.

    a high-strung, combustible nature.


noun

  1. a combustible substance.

    Trucks carrying combustibles will not be allowed to use this tunnel.

combustible British  
/ kəmˈbʌstəbəl /

adjective

  1. capable of igniting and burning

  2. easily annoyed; excitable

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

noun

  1. a combustible substance

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Derived Forms

Etymology

Origin of combustible

From the Late Latin word combūstibilis, dating back to 1520–30. See combust, -ible

Explanation

Combustible means "able to catch fire," like matches or the extremely dry forest floors that people sometimes forget are combustible — until they go up in flames. When the adjective combustible first entered the English language in the sixteenth century, it was used to describe things that burn easily. The word soon came to apply not only to objects that ignite but also to tempers that are prone to "catch fire" easily. If you’ve ever been around a person who has a combustible temper, you can understand the connection.

Keep Reading on Vocabulary.com

Vocabulary lists containing combustible

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.

Appeared in the October 3, 2025, print edition as 'Daniel Day-Lewis’s Combustible Return'.

From The Wall Street Journal • Oct. 2, 2025

Combustible materials: This pottery gets its color by chance.

From New York Times • Dec. 14, 2022

Combustible materials used to refurbish Grenfell were central to the chain of events in June 2017 that turned an ordinary kitchen fire into an inferno, an official inquiry said last month.

From Reuters • Nov. 11, 2019

Combustible cladding was not to be used on high-rise flats.

From BBC • Oct. 29, 2018

Combustible natural products inevitably make themselves noticed, as when a resinous log explodes in a campfire.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "combustible" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com