Saccular aneurysm: An aneurysm that resembles a small sack. A berry aneurysm is typically saccular. An aneurysm is a localized widening (dilatation) of an artery, vein, or the heart. At the area of an aneurysm, there is typically a bulge and the wall is weakened and may rupture. The word ôaneurysmö comes from the Greek ôaneurysmaö meaning ôa widening.ö
