Cholesterol (noun)

1. A waxy substance that is present in animal fats and oils and is important in the formation of cell membranes and the production of certain hormones.
2. A type of fat found in the blood that can build up in the walls of the arteries, blocking the flow of blood to the heart and increasing the risk of heart disease.

Origin:

Late 19th century: from cholest- (from greek khōlē "bile") + -ol + -sterol (from steroid).

Examples:

1. His cholesterol level was high.
2. She was told to lower her cholesterol.
3. He was prescribed medication to lower his cholesterol.
4. The diet was low in cholesterol.
5. The test showed high levels of LDL cholesterol.