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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

  • combustibility noun
  • combustibleness noun
  • combustibly adverb
  • uncombustible adjective

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.

On Tuesday, the Mets lost when combustible relief pitcher Devin Williams fell apart again, allowing Minnesota a go-ahead run and walking in a fifth run for kicks.

From The Wall Street Journal • Apr. 22, 2026

Residents would have to replace the first five feet of any combustible fencing or gates attached to their house with something made out of a noncombustible material, such as metal.

From Los Angeles Times • Apr. 18, 2026

They were behind the decision to bring in Tudor, the combustible Croatian with a chequered coaching career and no Premier League experience, to succeed the sacked Thomas Frank.

From BBC • Mar. 29, 2026

Evidence presented at hearings last week showed that government departments failed to effectively address residents' complaints about construction workers smoking on site and the use of combustible building materials during renovations.

From Barron's • Mar. 24, 2026

It was difficult to think of the ever-combative, highly combustible champion of the American Revolution as extraneous and invisible, but that is what the vice presidency had made him.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis