# aneurysm

/ˈænjʊˌɹɪzəm/ (US) · /ˈænjuːɹˌɪzəm/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/aneurysm
Updated: 2026-05-09

## Definition

a dangerous swelling or bulge in the wall of a blood vessel. If it breaks, it can cause serious bleeding inside the body.

For teachers: a localized, blood-filled dilation of a blood vessel caused by disease or weakening of the vessel wall. Often asymptomatic until rupture, which typically results in severe internal hemorrhaging.

## Examples

- The doctor found a small aneurysm during the brain scan.
- Doctors monitored the patient's aortic aneurysm for years to ensure it did not grow large enough to require surgery.
- While some aneurysms are congenital, others develop over time due to chronic hypertension or atherosclerosis, which gradually compromise the structural integrity of the arterial media.

## Usage notes

- Often paired with the name of the affected vessel, such as 'aortic' or 'cerebral'.

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