noun
combustion
kuhm-BUS-chuhn/kəmˈbʌstʃən/
Burning through a chemical reaction, usually with oxygen
The combustion of candle wax produces a flame above the wick.

Etymology
Latin comburere describes burning something up or consuming it by fire. The action noun names that process, preserving the same central idea in its chemical sense.
In context
it will burn only in presence of oxygen which is the combustion that whole process is known as combustion
More examples
- A steady supply of oxygen keeps combustion going.
- Incomplete combustion can produce dangerous carbon monoxide.
- The engine uses heat from combustion to move its pistons.
Forms
combust verb — To burn in a chemical reaction.
combustible adjective — Able to catch fire and burn.
Similar words
- burning
- The everyday term for the same chemical process.
- incineration
- Specifically burning something to ashes, often to dispose of waste.