aneurysm

American  

[an-yuh-riz-uhm] / ˈæn yəˌrɪz əm /

Or aneurism

noun

Pathology.

1. a permanent cardiac or arterial dilatation usually caused by weakening of the vessel wall.

---

aneurysm British  

/ ˈænjəˌrɪzəm /

noun

1. a sac formed by abnormal dilation of the weakened wall of a blood vessel

---

aneurysm Scientific  

/ ăn′yə-rĭz′əm /

1. A localized, blood-filled dilation of a blood vessel or cardiac chamber caused by disease, such as arteriosclerosis, or weakening of the vessel or chamber wall. A ruptured aneurysm results in hemorrhage and is often fatal.

---

Other Word Forms

• aneurismal
  adjective
• aneurismally
  adverb
• aneurysmal
  adjective
• aneurysmally
  adverb

Etymology

Origin of aneurysm

First recorded in 1650–60; from Greek aneúrysma “dilation,” equivalent to aneurys- (variant stem of aneurýnein “to dilate,” from an- an- ³ + eurýnein “to widen, broaden”; cf. eury-) + -ma, noun suffix

Explanation

Sometimes an artery wall weakens in a spot, causing a pouch-like bulge of pooled blood called an aneurysm. If it bursts, it can be life-threatening. While aneurysms can form anywhere, they are most common in the brain and cardiac areas. This is a very serious medical event that can cause injury and even death. Even though aneurysms are potentially deadly, people use the word sometimes in exaggerations. For example, if you see that someone is getting mad, you might say, "Don't have an aneurysm about it!" That just means something like "Take it easy! Don't get so excited."

Example Sentences

She has made it a yearly tradition to gather friends and family to join her in a 5K race to raise money for the Brain Aneurysm Foundation.

From The Wall Street Journal • Mar. 11, 2026

"Aneurysm patients do not usually have any symptoms and when they have symptoms it usually means that the aneurysm has either burst or about to burst," which he said wasusually fatal.

From BBC • Oct. 3, 2024

The yearly rate of rupture is about 10 in 100,000 people, according to the Brain Aneurysm Foundation.

From Fox News • Jul. 14, 2020

Numbers suggest ruptured brain aneurysms prove fatal in about 40 percent of cases, and 66 percent of survivors demonstrate some permanent neurological deficit, according to the Brain Aneurysm Foundation.

From Seattle Times • Jul. 17, 2018

Aneurysm of the aorta must in all cases of dysphagia be excluded, for the dilated aorta may be the sole cause of the condition, and its presence contraindicates esophagoscopy because of the liability of rupture.

From Bronchoscopy and Esophagoscopy A Manual of Peroral Endoscopy and Laryngeal Surgery by Jackson, Chevalier