combustion

noun

com·​bus·​tion kəm-ˈbəs-chən 

1

: an act or instance of burning

Smoke is produced during combustion.

2

: a usually rapid chemical process (such as oxidation) that produces heat and usually light

The carburetor mixes fuel with air for combustion.

also : a slower oxidation (as in the body)

3

: violent agitation : tumult

… periods of great social combustion alternating with quiescence …

—Kurt Andersen

combustive

kəm-ˈbə-stiv 

adjective

Examples of combustion in a Sentence

Combustion may occur at high temperatures.

This ratio of air to fuel results in better combustion.

Recent Examples on the Web

The result is fuel burned without localized rich pockets (which form soot), at lower overall combustion temperature (which reduces NOx), and with higher thermal efficiency (more muscle for the fuel used). —New Atlas, 23 Feb. 2026

Nationwide study Rather than relying on the combustion of fossil fuels, nuclear reactors harness the energy released through nuclear fission to generate heat. —Mrigakshi Dixit, Interesting Engineering, 23 Feb. 2026

The bZ Woodland competes with EVs like the Chevrolet Equinox EV, Hyundai Kona EV, VW ID and Volvo EX30 in addition to internal combustion models like the Equinox and Nissan Rogue and hybrid versions of the Honda CR-V, Hyundai Tucson, Kia Sportage and VW Tiguan. —Mark Phelan, USA Today, 20 Feb. 2026

When power plants burn coal to generate electricity, the combustion releases toxic metals, soot and other harmful substances as a byproduct ― even with the use of modern pollution control technology. —Connor Giffin, Louisville Courier Journal, 20 Feb. 2026

Word History

Etymology

Middle English combustioun "burning, calcination," borrowed from Anglo-French & Late Latin; Anglo-French combustion, borrowed from Late Latin combustiōn-, combustiō "burning up (of the dead or by the fires in hell)," from Latin combus-, variant stem of combūrere "to destroy with fire, reduce to ashes" + -tiōn-, tiō, suffix of verbal action — more at combust

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing combustion

• combustion chamber
• combustion engine
• external combustion engine
• internal combustion engine
• pre-combustion
• spontaneous combustion

Rhymes for combustion

• fustian

Kids Definition

combustion

noun

com·​bus·​tion kəm-ˈbəs-chən 

1

: an act or instance of burning

2

: a chemical process in which substances combine with oxygen

Medical Definition

combustion

noun

com·​bus·​tion kəm-ˈbəs-chən 

: a usually very rapid chemical process (as oxidation) that produces heat and usually light

also : a slower oxidation (as in the body)