Grease

The term grease is used to describe a semisolid lubricant. The main characteristic of grease is that they possess a high initial viscosity, which upon the application of shear, drops to give the effect of an oil-lubricated bearing of approximately the same viscosity as the base oil used in the grease.

The function of grease is to stay in contact with and lubricate moving surfaces without leaking out under the force of gravity, centrifugal action or being squeezed out under pressure. Its major importance is that it retains its properties under shear forces at all temperatures it experiences during use