Lubricant

Lubrication is the process employed to reduce wear of one or both surfaces in close proximity and moving relative to each other by interposing a substance called Lubricant between the surfaces to carry the load between the opposing surfaces. The interposed Lubricant film can be solid, a solid/liquid dispersion, liquid-liquid dispersion

In the most common case the applied is carried by the pressure generated between the fluid due to the frictional viscous resistance to motion of the lubricating fluid between the surfaces.

Lubrication can also describe the phenomenon such reduction of wear occurs without human intervention

When we talk about lubrication smooth continuous equipment operation is assumed, with only mild wear, and without excessive stresses within the lubricated conjunctions to cause seizure at the conjunction, or break of any part of the equipment, and when such a catastrophic event does occur it means that the lubrication has broken down.