def·​la·​grate | \ ˈde-flə-ˌgrāt How to pronounce deflagrate (audio) \
deflagrated; deflagrating

Definition of deflagrate

transitive verb

: to cause to deflagrate — compare detonate sense 1

intransitive verb

: to burn rapidly with intense heat and sparks being given off

Keep scrolling for more

Other Words from deflagrate

deflagration \ ˌde-​flə-​ˈgrā-​shən How to pronounce deflagration (audio) \ noun

Did You Know?

Deflagrate combines the Latin verb flagrare, meaning "to burn," with the Latin prefix de-, meaning "down" or "away." Flagrare is also an ancestor of such words as conflagration and flagrant and is distantly related to fulgent and flame. In the field of explosives, deflagrate is used to describe the burning of fuel accelerated by the expansion of gasses under the pressure of containment, which causes the containing vessel to break apart. In comparison, the term detonate (from the Latin tonare, meaning "to thunder") refers to an instant, violent explosion that results when shock waves pass through molecules and displace them at supersonic speed. Deflagrate has been making sparks in English since about 1727, and detonate burst onto the scene a couple of years later.

First Known Use of deflagrate

circa 1727, in the meaning defined at transitive sense

History and Etymology for deflagrate

Latin deflagratus, past participle of deflagrare to burn down, from de- + flagrare to burn — more at black entry 1

Keep scrolling for more

Learn More about deflagrate

Time Traveler for deflagrate

Time Traveler

The first known use of deflagrate was circa 1727

See more words from the same year

Listen to Our Podcast about deflagrate

Statistics for deflagrate

Cite this Entry

“Deflagrate.” The Dictionary, Merriam-Webster Inc., Accessed 20 January 2020.

More from Merriam-Webster on deflagrate

Rhyming Dictionary: Words that rhyme with deflagrate

Comments on deflagrate

What made you want to look up deflagrate? Please tell us where you read or heard it (including the quote, if possible).


not to be intimidated or subdued

Get Word of the Day daily email!

Test Your Vocabulary

The Eponym Quiz

  • rubens painting
  • Which is the best synonym of bowdlerize?
Spell It

Can you spell these 10 commonly misspelled words?


Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!