An abdominal aortic aneurysm (AAA) is a bulge that forms in the wall of the aorta, the largest blood vessel in the body, as it passes through the abdomen. This condition occurs when the aortic wall weakens, leading to an increased risk of rupture, which can be life-threatening. Risk factors for developing an AAA include smoking, high blood pressure, and a family history of the condition. Symptoms may not be present until the aneurysm becomes large or ruptures, making regular check-ups important for early detection, especially in at-risk individuals.