Grease

Grease is a solid or semisolid lubricant made by dispersing a thickening agent, commonly a soap, through a base of mineral, synthetic or vegetable oil. Under mechanical stress it becomes shear-thinning, meaning its viscosity drops so that it behaves like the liquid oil it is built from, which lets it lubricate moving parts even though it holds its shape at rest. This makes grease well suited to machinery that is lubricated infrequently or cannot retain a free-flowing oil, and beyond lubrication it also acts as a sealant, keeping water and contaminants out of mechanical components. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/