What is the term for a fatty deposit that forms in the walls of blood vessels?

The term for a fatty deposit that forms in the walls of blood vessels is plaque. Plaque develops when fat, cholesterol, and other substances accumulate in the blood vessel walls, leading to a narrowing and hardening of the arteries, which can impede blood flow. This process is a significant factor in cardiovascular diseases.

In the context of the other terms, thrombus refers to a blood clot that can form in a blood vessel, which is a different concept from a fatty deposit. Atherosclerosis describes the condition characterized by the buildup of plaque in the arteries but does not refer specifically to the fatty deposits themselves. Cholesterol is a type of fat found in the body that can contribute to plaque formation, but it does not specifically denote the deposits that form in blood vessel walls. Therefore, using the term plaque accurately identifies the deposits formed in the walls of blood vessels, making it the correct choice.