In thick-film lubrication, the moving/sliding surfaces are separated from each other by a thick-film of fluid, (at least 1000 Å thick), so that direct surface-to-surface contact and welding of junctions rarely occurs.

The lubricant film covers/fills the irregularities of the sliding/moving surfaces and forms a thick layer in between them, …

It is the condition of lubrication where two surfaces of the bearings are completely separated by the film of liquid, in this type of lubrication, the load is taken completely by the oil film.