Baffle

1-A part of a structure used to impede, regulate, or alter the rate or direction of flow of a fluid, light, or sound.

2-(air-cooled Engine Component)A sheet metal shield used to direct the flow of air between and around the cylinders of an air-cooled reciprocating engine. Forcing this air to flow through the fins on the cylinders removes the maximum amount of heat from the engine.

3-(fuel Tanks)A series of baffles, or partitions, inside an aircraft fuel tank. These baffles have holes in them that allow the fuel to feed to the tank outlet, but prevent the fuel from surging enough to uncover the outlet. Aircraft fuel tanks carry such large quantities of fuel that the sloshing (surging back and forth) of the fuel in a partially full tank could cause severe control problems.