English Reference

Word

combustible

Phoneticscom·bustible

UK/kəmbˈʌstəbəl/

Definition

n. a substance that can catch fire and burn easily. You use this to describe things like paper, wood, or gasoline.

n. a substance that is capable of undergoing combustion. Often used in technical or industrial contexts to describe materials that pose a fire hazard.

Examples

“Wood is a common combustible used for heating.”

“The warehouse must be kept clear of all combustibles to meet local fire safety regulations.”

“While the structural steel is designed to withstand extreme heat, the surrounding combustibles were quickly consumed by the initial flames, accelerating the spread of the fire.”

Examples

simple

“Wood is a common combustible used for heating.”

contextual

“The warehouse must be kept clear of all combustibles to meet local fire safety regulations.”

complex

“While the structural steel is designed to withstand extreme heat, the surrounding combustibles were quickly consumed by the initial flames, accelerating the spread of the fire.”

Real-World Examples

“The beetles stripped plants of their leaves and left combustible woody stems, he said.”
BBC News · 7 Aug 2026
“The area within 5 feet of a home, known as Zone 0 , should be kept free of combustible materials.”
The Conversation · 3 Aug 2026
“Other areas had gone without fire for more than 100 years, allowing dead wood, shrubs, and other combustible material to accumulate.”
ScienceDaily · 26 Jul 2026

Etymology

From Middle French combustible, equivalent to combust + -ible.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Word family

combustibleNouncombustionNoun

This entry

Level
C1 · Advanced
Frequency
Occasional
Updated

Scan code

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English Reference