The operation of fire on inflammable substances; or according to modern chimistry, the union of an inflammable substance with oxygen, attended with light, and in most instances, with heat. In the combustion of a substance, heat or caloric is disengaged, and oxygen is absorbed. This theory of Lavoisier being found somewhat defective, the following definition is given. Combustion is the disengagement of heat and light which accompanies chimical combination. Combustion cannot be regarded as dependent on any peculiar principle or form of matter, but must be considered as a general result of intense chimical action.

In popular language, a burning; the process or action of fire in consuming a body, attended with heat, or heat and flame; as the combustion of wood or coal.

Conflagration; a great fire. Hence, from the violent agitation of fire or flame,

Tumult; violent agitation with hurry and noise; confusion; uproar.