combustible

/kəmˈbʌs.tə.bəl/
able to catch fire

The laboratory strictly prohibits storing combustible materials near open flames.

The lab bans keeping flammable substances close to fire sources.


Engineering
technical

Capable of igniting and burning easily.

Petroleum products are highly combustible and require careful handling.

Oil-based fuels burn easily and must be stored with caution.

Often used in safety regulations and technical contexts to describe materials prone to fire.

figurative

Likely to provoke anger or conflict.

His speech contained combustible rhetoric that sparked protests.

His inflammatory words incited public outrage.

Used metaphorically to describe language or actions that may escalate tension.

Pro Tip

Avoid confusion with 'inflammable'

'Inflammable' means the same as 'flammable' (able to catch fire), despite the prefix 'in-' suggesting negation. Use 'non-flammable' for clarity.

Gold Rule

Technical vs. figurative use

Use 'combustible' for physical materials in engineering/safety contexts. For metaphorical escalation of conflict, pair it with terms like 'rhetoric' or 'situation'.

Word Origin

From Latin *combustibilis*, meaning 'capable of being burned,' from *combustus* (past participle of *combūrere*, 'to burn up'), from *com-* (intensive) + *ūrere* ('to burn').

Usage Notes

In everyday speech, 'flammable' is more commonly used than 'combustible,' though both are correct. 'Combustible' is preferred in technical and scientific contexts.

Word Breakdown

com-
intensive prefix
prefix
+
-bust-
to burn
root
+
-ible
able to be
suffix
English Dictionary