Combustion \Com*bus"tion\ (?; 106), n. [L. combustio: cf. F. combustion.]

1. The state of burning.

2. (Chem.) The combination of a combustible with a supporter of combustion, producing heat, and sometimes both light and heat.

Combustion results in common cases from the mutual chemical action and reaction of the combustible and the oxygen of the atmosphere, whereby a new compound is formed. --Ure.

Supporter of combustion (Chem.), a gas, as oxygen, the combination of which with a combustible, as coal, constitutes combustion.

3. Violent agitation; confusion; tumult. [Obs.]

There [were] great combustions and divisions among the heads of the university. --Mede.

But say from whence this new combustion springs. --Dryden.

Source: Webster's Revised Unabridged Dictionary (1913)