Final answer:
The combining form arter/o means artery, a blood vessel that carries blood away from the heart and is critical to the circulatory system.
Step-by-step explanation:
The combining form arter/o refers to an artery, which is a blood vessel that takes blood away from the heart. Arteries are an essential part of the circulatory system, branching into smaller vessels known as arterioles, which in turn lead to capillaries where nutrient and waste exchange occurs. Atherosclerosis is a condition where fatty plaques build up in the coronary arteries of the heart, which can lead to serious health problems.