The original Definition of ASTM of Grease was "A” solid or semi solid combination of petroleum products and a soap or mixtures of soaps with or without fillers, suitable for certain types of lubrication.
Subsequent technological advances have led to the use of synthetic lubricating fluids on the one hand and non-soap thickener’s on the other hand.
Current - Modified Definition of Grease is "A solid or semi solid product of dispersion of thickening agent in liquid lubricant. Other ingredients imparting special properties may be included”.
Most greases are in fact is a combination of petroleum oils and metallic soaps.

The original Definition of ASTM of Grease was "A” solid or semi solid combination of petroleum products and a soap or mixtures of soaps with or without fillers, suitable for certain types of lubrication.
Subsequent technological advances have led to the use of synthetic lubricating fluids on the one hand and non-soap thickener’s on the other hand.
Current - Modified Definition of Grease is "A solid or semi solid product of dispersion of thickening agent in liquid lubricant. Other ingredients imparting special properties may be included”.
Most greases are in fact is a combination of petroleum oils and metallic soaps.