what is the definition of vapor
Fog is an example of vapor. Fog is an example of vapor. Vapor is a gas or moisture floating in the air. An example of vapor is fog. Vapor is defined as to give off gas or water moisture. An example of vapor is for water to give off steam when it boils.
1 The gaseous state of a substance that is liquid or solid at room temperature. 2  A faintly visible suspension of fine particles of matter in the air, as mist, fumes, or smoke. 3  A mixture of fine droplets of a substance and air, as the fuel mixture of an internal-combustion engine.