Stenosis – Wikipedia

A stenosis (from Ancient Greek στενός, “narrow”) is an abnormal narrowing in a blood vessel or other tubular organ or structure. It is also sometimes called a stricture (as in urethral stricture).. Stricture as a term is usually used when narrowing is caused by contraction of smooth muscle (e.g. achalasia, prinzmetal angina); stenosis is usually used when narrowing is caused by lesion …

https://en.wikipedia.org/wiki/Stenosis