deflagrate
Very lowTechnical / Scientific
Definition
Meaning
To burn rapidly with intense heat and flame, but not explosively; to cause (a substance) to burn suddenly.
In physics and chemistry, to burn with a sudden, intense flame that propagates through the material at subsonic speed, distinguishing it from detonation.
Linguistics
Semantic Notes
Specifically denotes a fast, intense combustion that spreads through thermal conduction, not a shockwave. The result is fire, not an explosion.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning or usage. The word is used identically in technical contexts in both varieties.
Connotations
Extremely technical, with primary connotations to chemistry, pyrotechnics, and materials science. No cultural or everyday connotations.
Frequency
Extremely rare in general use; almost exclusively found in technical literature. Frequency is identical and minimal in both BrE and AmE.
Vocabulary
Collocations
Grammar
Valency Patterns
Noun + deflagrate + (Adverb of manner)It is possible to deflagrate + NounVocabulary
Synonyms
Neutral
Weak
Vocabulary
Antonyms
Usage
Context Usage
Business
Never used.
Academic
Used in chemistry, physics, and materials science papers to describe specific combustion behavior.
Everyday
Virtually never used. An unknown word for the vast majority of native speakers.
Technical
Primary domain of use. Describes the subsonic combustion of propellants, pyrotechnic compositions, or certain dusts.
Examples
By Part of Speech
verb
British English
- The laboratory safety sheet warned that the finely-divided powder could deflagrate if exposed to an open flame.
- Under those conditions, the mixture will deflagrate rather than detonate.
American English
- The accident report concluded that the propellant began to deflagrate, causing the intense fire.
- Researchers observed the sample deflagrate at approximately 400 degrees Celsius.
adjective
British English
- The deflagrating spoon is a standard piece of chemistry equipment for safe combustion demonstrations.
American English
- They studied the material's deflagration characteristics to improve safety protocols.
Examples
By CEFR Level
- Certain metals in powder form can deflagrate violently.
- The chemical is designed to deflagrate, not explode, for a controlled burn.
- The distinction between a substance that will deflagrate and one that will detonate is critical for explosive ordinance disposal.
- The experiment demonstrated how the fuel-air mixture would deflagrate at a predictable rate under standard pressure.
Learning
Memory Aids
Mnemonic
Think: 'The FLAME RATE of combustion defines DEFLAGRATE' – it's about the speed (rate) of a flame (flagr- from Latin 'flagrare', to burn).
Conceptual Metaphor
CONTROLLED FIRE IS A RAPID CONSUMER (vs. explosive destruction).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with 'дефлаграция' (same term in Russian scientific contexts). The common Russian word 'гореть' (to burn) is too generic; 'deflagrate' implies specific, fast, scientific combustion.
- It is not 'взрываться' (to explode), which is closer to 'detonate'.
Common Mistakes
- Using it to mean 'explode'.
- Using it in non-technical contexts where 'burn', 'catch fire', or 'ignite' would be appropriate.
- Misspelling as 'deflagrate' (correct) vs. 'deflagerate' (incorrect).
Practice
Quiz
What is the key technical distinction of 'deflagrate'?
FAQ
Frequently Asked Questions
'Deflagrate' means to burn rapidly with a flame front moving slower than the speed of sound (subsonic). 'Detonate' means to explode with a shockwave moving faster than sound (supersonic).
No, it is a very rare, highly technical term used almost exclusively in scientific fields like chemistry, pyrotechnics, and safety engineering.
No, that would be incorrect and unnatural. Use 'engulfed in flames', 'burned rapidly', or 'was consumed by fire' instead.
It comes from the Latin 'deflagratus', past participle of 'deflagrare', meaning 'to burn down', from 'de-' (down) + 'flagrare' (to burn).