What is the term for the abnormal enlargement of an artery due to a weakening of the vessel wall?

The term for the abnormal enlargement of an artery due to a weakening of the vessel wall is aneurysm. An aneurysm occurs when the pressure of the blood flow causes a localized section of the arterial wall to bulge or balloon out. This weakening can be caused by various factors including hypertension, atherosclerosis, or genetic conditions, which compromise the structural integrity of the vessel wall. If left untreated, an aneurysm poses a significant risk as it can rupture, leading to life-threatening internal bleeding.

Embolism refers to the blockage of a blood vessel usually caused by a clot or debris that travels through the bloodstream. Thrombosis involves the formation of a blood clot within a blood vessel, leading to blockage of blood flow, while vasculitis is the inflammation of blood vessels, which can affect their function but does not specifically refer to the dilation of the vessel wall. Understanding these definitions helps clarify why aneurysm is the appropriate term for this condition.