What is the term for a weakened section of an arterial wall that begins to dilate?

The correct term for a weakened section of an arterial wall that begins to dilate is an aneurysm. An aneurysm occurs when the arterial wall becomes weakened, usually due to factors such as hypertension, atherosclerosis, or genetic conditions, causing it to bulge or expand outward. This dilation can pose significant health risks, as the affected artery may rupture, leading to potentially life-threatening internal bleeding.

The other terms are distinct medical conditions: an embolism refers to a blockage in a blood vessel caused by a foreign body, such as a blood clot or fat globule, that travels through the bloodstream. Thrombosis specifically pertains to the formation of a blood clot within a blood vessel that can impede blood flow. Stenosis indicates a narrowing of a blood vessel or heart valve, which can lead to reduced blood flow, but does not involve dilation or weakening of the wall. Understanding these specific definitions is crucial for proper diagnosis and treatment in emergency medical situations.