noun A device for delivering pressurized air in a controlled quantity to a controlled location. At its most simple terms a bellows is a container which is deformable in such a way as to alter its volume which has an outlet or outlets where one wishes to blow air.
When wood fires were common, so were bellows for helping start them.
noun Any flexible container or enclosure, as one used to cover a moving joint.
noun The lungs.
noun Flexible, light-tight enclosures connecting the lensboard and the camera back.
noun That which fans the fire of hatred, jealousy, etc.
verb To operate a bellows; to direct air at (something) using a bellows.