[UPDATED] These two terms are synonyms, but they have different etymology. [Stenosis] arises from the Greek [στενός] (sten?s) meaning "narrow". Since the suffix [-osis] means "condition of", the word [stenosis] means a "condition of narrowing".

The synonym [stricture] arises from the Latin term [strictus] meaning "narrow", "restricted" or "constriction". Both terms refer to the narrowing of an anatomical structure, as in "coronary artery stenosis", or the "stenosis of an anastomosis".

A common mistake is to confuse [stenosis] and [stricture] with "blockage" or "obstruction". Although an stenotic vessel is partially obstructed, there is still flow and it is not a complete obstruction.

Sources:
1. "The Language of Medicine" John H. Dirckx Pub: Harper & Row 1976
2. "Medical Meanings" Haubrich, William S. Am Coll Phys Philadelphia 1997
3. "The origin of Medical Terms" Skinner, AH, 1970

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