Grease is a thick, oily substance which is put on the moving parts of cars and other machines in order to make them work smoothly.

If you grease a part of a car, machine, or device, you put grease on it in order to make it work smoothly.

Grease is an oily substance that is produced by your skin.

Grease is animal fat that is produced by cooking meat. You can use grease for cooking.

If you grease a dish, you put a small amount of fat or oil around the inside of it in order to prevent food sticking to it during cooking.